Anti-caster killer creature

[arkangel111]

Looking to see if anyone knows of or has/can created a caster killer creature. Hoping for a magical beast or some such. Basically want it to actively hunt mages, so some immunities, maybe Su antimagic field or such. A draining attack that steals buffs or even eats spellslots. If its not PF kosher I'll be updating it I am building this world in a 3.P environment. I am also having 100% transparency between magic/psionics/divine

Hoping to use it as a basis for my upcoming homebrew world where an organization uses these as pets to kill mages/psions/clerics or what not.

[Jormengand]

The shadow of nothing, a lethal beastie that lives in a specially-prepared area called a field of woe, may do the trick:


A Field of Woe is one of the most powerful anti-magic inventions ever to come to be. It is set up in an area consisting of up to 20 10-foot squares, which must form a continuous zone with no gaps, and its domain extends 1000 feet skywards unless a large physical barrier stops it. Whenever a creature casts a spell in a Field of Woe, the spell is destroyed: it does not resolve and become countered, it does not fail, it simply does not come to pass. The spell slot is wasted. So too is it for psionic powers, and spell-like, psi-like and supernatural abilities. Creatures who bring constant-effect magical items or spell effects into the field, or enter with a constant-effect supernatural ability, find that they simply fail once they are brought in: weapons and armour are still usable, and even masterwork, and any constant-effect item that is taken out of the field works once more after a round (assuming, and to the extent that, it worked prior to entry). Items or supernatural abilities that must be activated simply do not work and their charges are wasted.

A Field of Woe gains power points equal to the caster/manifester/inventor level of each spell, power, spell-like or psi-like ability, activated supernatural ability, or magic item charge it consumes, but none for suppressing constant-effect items or supernatural abilities. If there is none, use the creator or user's hit dice as appropriate.

A Field of Woe acts precisely once when its power points were raised from zero to a number greater than zero, and it does so one round after this occurred, before the transgressor's initiative count (Suppose a wizard enters and tries to cast a spell, then a cleric enters and does the same, then the Field of Woe will act just before the wizard has another chance to act). It is not subject to its own effects, and the creature it summons is not either, but nor can Fields of Woe be built so as to overlap or both will fail to operate. When a Field of Woe acts, it raises a barrier around its edge, and summons a Shadow of Nothing directly in front of the creature who set it off, or as close as possible if it cannot be placed. Given that a Shadow of Nothing can fly, it is almost certain that it can be placed in the field. If not, the field explodes, dealing damage equal to the number of power points it had times seven to each creature in the area.

Shadows of Nothing and the walls around the Field of Woe share a hit point total, which is also equal to the number of power points the Field of Woe has: as one increases or decreases, so too do the other two. By destroying the wall or the Shadow of Nothing, the Field of Woe can be left. The wall's AC is always that of the Shadow of Nothing, although it's always flat-footed because it's a wall. Destroying a Field of Woe while it is active is impossible, but when it is inactive a creature can attempt to destroy it with a weapon. It has a hardness of 10 and 100 hit points per square, but destroying any of the squares renders the whole lot inoperable.

A Shadow of Nothing with no hit points is destroyed. A Shadow of Nothing without anyone to attack shatters, as does the wall, and the Field of Woe is reduced to zero power points.

Shadow of Nothing
Size/Type: Huge
Hit Dice: * (10 effective hit dice)
Initiative: +4 +*/5 + */20
Speed: 20+* feet (4+*/5 squares), Fly 20+* feet (Clumsy)
Armor Class: 8 + 3*/10 (+*/4 +*/20 Dex -2 Size) touch 8+3*/10 flat-footed 8+*/4
Base Attack/Grapple: +10/+12+*/20
Attack: Horror +8+*/20 melee (1d6+(*+*/20))
Full Attack: 2 Horrors (+8+*/20)/(+3+*/20) melee (1d6+(*+*/20))
Space/Reach: 20 ft/20 ft
Special Attacks: Drain Magic
Special Qualities: A Shadow in the World, Nihil Est
Saves: For +7 + */10 Ref +7 + */20+*/10 Will +7 + */20+*/10
Abilities: Str 10+*/10 Dex 10+*/10 Con - Int 10+*/10 Wis 10+*/10 Cha 10+*/10

A Shadow of Nothing attempts to kill anything in its field. It cannot be commanded or controlled, speaks no languages and understands all of them, and only uses this comprehension to ensure the total destruction of the opposition. Shadows of Nothing do not leave their fields, nor do anything but kill people.

Drain Magic: Whenever a Shadow of Nothing hits with a melee attack, it removes the target's highest level spell slot, or power points equal to the number of power points that creature can spend at once, whichever gives it more power points. If it gets the same number from each, it chooses randomly. It then absorbs that many power points, or twice the spell's level in power points, into the field. If there are multiple spell slots that could be chosen, the spell slot lost is chosen randomly.

A Shadow in the World: A Shadow of Nothing gets more powerful the more power points there are in the field. This gets weird fast.

The Shadow of Nothing's Hit Points and Movement Speed (in feet) scale directly with the Field of Woe's power points, as does the damage its horror deals (though this also scales with strength, so the scaling is 21/20 times the number of power points). Its untyped bonus to AC scales with a quarter of its power points. Its initiative scales with 1/5 of its power points, but also with dexterity. Its saves scale with 1/10 of its power points and the relevant ability score. The ability scores scale with 1/10 of its power points.

Nihil Est: A Shadow of Nothing has no types or subtypes. It lacks an alignment. Anything that requires an alignment, or type, or subtype to function is not effective against a Shadow of Nothing. A Shadow of Nothing is not a living creature, nor a dead one, nor an object, nor a construct. Shadows of Nothing don't go away in an antimagic field even if you can get one close enough.

They are only actually possible to make for a high-level inventor, but I'm sure they could be adapted.

[arkangel111]

Umm... not sure if that will work... it sounds more like an area spell that also summons creatures. I was hoping for something perhaps based off of a Dire creature with an AMF that it projects. Just an anti-caster creature. Hunts in packs and eats the magical energy. I really can't believe it doesn't already exist in 3.5, let alone that someone hasn't homebrewed one. I doubt I am the first one to think of such.

[Jormengand]

Thaumavore
Size/Type: Large Magical Beast
Hit Dice: 10d10+30 (85 hp)
Initiative: +0
Speed: 30 ft. (6 squares), fly 60 ft. (poor)
Armor Class: 20 (-1 size, +11 natural), touch 9, flat-footed 20
Base Attack/Grapple: +10/+20
Attack: Gore +15 melee (2d6+6)
Full Attack: Gore +15 melee (2d6+6) and 2 claws +10 melee (1d6+3)
Space/Reach: 10 ft./5 ft.
Special Attacks: Magebane
Special Qualities: Magic Sense, Antimagic Field
Saves: Fort +10, Ref +7, Will +3
Abilities: Str 23, Dex 10, Con 17, Int 10, Wis 11, Cha 11
Skills: Intimidate +8, Listen +11, Spot +1
Feats: Alertness, Cleave, Flyby Attack, Power Attack
Environment: None (Artificial)
Organization: None (Artificial)
Challenge Rating: 7
Treasure: Standard
Alignment: Always neutral
Advancement: 11-15 HD (Large); 16-30 HD (Huge)
Level Adjustment: -

Thaumavores are creatures who have grown used to the taste of magi, often growing from the great beasts used to hunt them, into a creature that does nothing but prey on magic-users. Thaumavores would originally have spoken four languages, but have lost two of them to insanity. They now speak only common, and one other language, usually the language of the community who created the thaumavore.

Thaumavores are never encountered in the wild, and are organised only by the community who created them.

Magebane (Ex): A creature struck by a thaumavore loses spells, powers, or other magical or psionic abilities as though it had taken 1d3 negative levels each time.

Magic Sense (Ex): A thaumavore instinctively knows the location of each spell, power, caster or manifester within 120 feet, even if the thaumavore doesn't have line of effect to that creature.

Antimagic Field (Ex): A thaumavore constantly radiates an antimagic field, only the area has a 20 foot radius.

[AtlasSniperman]

I know he basically already gave you what you want. But I thought I'd chuck in my own creation just for a little variety for you. Sorry, I warn you I am not great at creating monsters.



Leimite Swarm
Tiny Magical Beast (Swarm)
Hit Dice: 7d8-7(24hp)
Initiative: +10
Speed: 10ft. (2 squares), fly 40ft.(average)
Armor Class: 12 ( +10 Dex, +2 size), touch , flat-footed
Base Attack/Grapple: -/-
Attack: Swarm (Magic devouring)
Full Attack: Swarm (Magic devouring)
Space/Reach: 10ft./0ft.
Special Attacks: Magic devouring, distraction
Special Qualities: Half damage from slashing and piercing, Swarm traits, Magic absorption, Blindsight, Dimensional drag.
Saves: Fort +1, Ref +12, Will +8
Abilities: Str 1, Dex 30, Con 8, Int -, Wis 17, Cha 2
Skills: -
Feats: -
Environment: Any
Organization: Solitary, force(2-7 swarms), or devastation(11-20 swarms)
Challenge Rating: UNKNOWN ATM. Though it is plausible that a leimite swarm would be less of a challenge for lower level party.
Treasure: None
Alignment: Neutral
Advancement: None

An undulating cloud of speckled, slightly luminous insects; halfway between a mantis and a rhinoceros beetle, bears down on the area.

A leimite swarm is a mass of magic-eating insects. Individual Leimites are almost never witnessed. While unaffected by magic, leimite swarms are still physical creatures and can be contained in any cage that should be capable of holding a similar number of rats.

Combat
A leimite swarm seeks to devour any and all magic it encounters. A swarm deals damage to magic casters and magical equipment being used.
Magic absorption(Su): A leimite swarm is immune to magic of all kind. Any magical or psionic effect that touches a leimite swarm grants the swarm 2 hp per spell level. Excess healing above base HP is treated as bonus hp. This bonus HP is the first to be lost when taking damage and any excess fades 1 hour after the last time damage was taken. No magical effect can prevent this; even antimagic fields are not immune. Weapons with a magical enhancement, heal the swarm by their magical enhancement per attack (i.e. a +2 Warhammer deals 1d8-2 damage before adding user strength)
Magic Devouring(Su): Unlike other swarms, Leimite swarms do not do regular damage. Instead, every round each creature within the space of a leimite swarm that is capable of casting spells, spell-like abilities, Psionic powers, takes 1 point of ability damage. This ability damage targets the creatures main casting stat. Magic items within the space of a leimite swarm take a point of damage each round, ignoring hardness and magical deflections.
Blindsight(Ex): Leimite swarms only see magical auras(even those disguised by the Nystul's Magic Aura spell). A swarm will ignore all living creatures that do not possess such an aura.
Dimensional drag(Su): Any spell that teleports a creature from within 30 feet of a Leimite swarm, automatically takes the swarm with, regardless of the limitations of the magic in question.

[Eno Remnant]

I don't know about homebrew options, but there's a first-party creature called the balhannoth in Monster Manual IV (I think), which has antimagic tentacles and likes to eat magical items. They're more of an ambush creature than a hunter, and they tend to be solitary, but I'm sure you could modify it to suit your needs.

[Debihuman]

Thaumavore needs a time limit on how long the magebane ability lasts and there should probably be a save for it. Environment should be any as artificial doesn't have any real meaning since you didn't mention it in the creature's description. Looks like organization should be Solitary rather than None. If you are going to add new terms, the least you could do is define them.

Debby

[AtlasSniperman]

No opinions on the Leimites Debi? YAY I got off; stupid-free!

[Zaydos]

I don't have any magic eating Magical Beasts but I do have a few (http://www.giantitp.com/forums/showsinglepost.php?p=10915000&postcount=810) mage hating (http://www.giantitp.com/forums/showsinglepost.php?p=9412922&postcount=4) true dragons (http://www.giantitp.com/forums/showsinglepost.php?p=9523460&postcount=375) and beholder-kin (http://www.giantitp.com/forums/showsinglepost.php?p=17020069&postcount=7).

The beholder kin includes a reptilian dire animal-like aberration with a natural anti-magic field which accelerates spell durations within it.

Also bats that eat spells (http://peanutdracolich.tumblr.com/post/122483571742/tour-of-a-mages-menagerie-pt-5).

[Jormengand]

Thaumavore needs a time limit on how long the magebane ability lasts and there should probably be a save for it. Environment should be any as artificial doesn't have any real meaning since you didn't mention it in the creature's description. Looks like organization should be Solitary rather than None. If you are going to add new terms, the least you could do is define them.

Debby

There aren't saves for enervation or energy drain either, and I don't see that as a failing of either. There is no duration for losing the spells: you can only get them back by preparing new spells. The creature does not have a natural environment or a normal organisation. Someone could decide to throw a thaumavore into a church or three hundred and twenty-seven up a mountain. I think it should be obvious what artificial means.

[AtlasSniperman]

There aren't saves for enervation or energy drain either, and I don't see that as a failing of either. There is no duration for losing the spells: you can only get them back by preparing new spells. The creature does not have a natural environment or a normal organisation. Someone could decide to throw a thaumavore into a church or three hundred and twenty-seven up a mountain. I think it should be obvious what artificial means.

States that something isn't defined clearly in many a thread.
Defends his own ambiguity when it's called into question.

[Jormengand]

States that something isn't defined clearly in many a thread.
Defends his own ambiguity when it's called into question.

I don't know what you're trying to tell me. Also, I don't know who "He" is, given that the only person in this thread with a male gender icon other than you is Zaydos, and he hasn't stated anything.

[TheTeaMustFlow]

Just throw Beholders at them. Not to say Beholders aren't anti-everything, but an antimagic eye covereth a multitude of sins.

[Debihuman]

There aren't saves for enervation or energy drain either, and I don't see that as a failing of either. There is no duration for losing the spells: you can only get them back by preparing new spells. The creature does not have a natural environment or a normal organisation. Someone could decide to throw a thaumavore into a church or three hundred and twenty-seven up a mountain. I think it should be obvious what artificial means.

The effects of energy drain and enervation only last 24 hours. That's why there is no save. Actually here's the full text on Energy Drain:

Energy Drain is in SRD under special abilities: "Negative levels remain until 24 hours have passed or until they are removed with a spell, such as restoration. If a negative level is not removed before 24 hours have passed, the affected creature must attempt a Fortitude save (DC 10 + ½ draining creature’s racial HD + draining creature’s Cha modifier; the exact DC is given in the creature’s descriptive text). On a success, the negative level goes away with no harm to the creature. On a failure, the negative level goes away, but the creature’s level is also reduced by one. A separate saving throw is required for each negative level." They don't repeat this text every time in the MM and SRD because it's standard.

This is my problem: "A creature struck by a thaumavore loses spells, powers, or other magical or psionic abilities as though it had taken 1d3 negative levels each time." Your target isn't losing levels, it's only losing "spells, powers, or other magical or psionic abilities" so you need to state when and how those come back because it's not exactly like ability drain so presumably this could be different too. it was just lazy design not to say that the abilities return in 24 hours -- just like [I]enervation and ability drain. I can guess that's what you mean but that's an assumption and DMs hate not having RAW.

Furthermore, a stat block with no description of the creature makes it harder to use. This is why the old Ecology articles in Dragon Magazine were so popular. We have no idea what this creature looks like other than what can be inferred from the stat block. It has 2 claws and a gore attack. That's a lot of wiggle-room for design. Form generally follows function. So it's killing mages but not lapping up magical energy from spellbook and scrolls, just suppressing them with its anti-magic field. That's a great hook.

It should have a language or two (Int 10).

And now I'd be curious about the beasts used to hunt them--ooooh a tie-in. Very nice.

The whole reason that this critique is so long is because I really like this critter (probably more than you do :smalltongue: )

Debby

[Jormengand]

The effects of energy drain and enervation only last 24 hours. That's why there is no save. Actually here's the full text on Energy Drain:

Energy Drain is in SRD under special abilities: "Negative levels remain until 24 hours have passed or until they are removed with a spell, such as restoration. If a negative level is not removed before 24 hours have passed, the affected creature must attempt a Fortitude save (DC 10 + ½ draining creature’s racial HD + draining creature’s Cha modifier; the exact DC is given in the creature’s descriptive text). On a success, the negative level goes away with no harm to the creature. On a failure, the negative level goes away, but the creature’s level is also reduced by one. A separate saving throw is required for each negative level." They don't repeat this text every time in the MM and SRD because it's standard.

This is my problem: "A creature struck by a thaumavore loses spells, powers, or other magical or psionic abilities as though it had taken 1d3 negative levels each time." Your target isn't losing levels, it's only losing "spells, powers, or other magical or psionic abilities" so you need to state when and how those come back because it's not exactly like ability drain so presumably this could be different too. it was just lazy design not to say that the abilities return in 24 hours -- just like [I]enervation and ability drain. I can guess that's what you mean but that's an assumption and DMs hate not having RAW.

What I mean is:


If the victim casts spells, she loses access to one spell as if she had cast her highest-level, currently available spell. (If she has more than one spell at her highest level, she chooses which she loses.) In addition, when she next prepares spells or regains spell slots, she gets one less spell slot at her highest spell level.

That doesn't have a duration. It doesn't need a duration. It lasts until the next time the creature next prepares spells or regains spell slots.


Furthermore, a stat block with no description of the creature makes it harder to use. This is why the old Ecology articles in Dragon Magazine were so popular. We have no idea what this creature looks like other than what can be inferred from the stat block. It has 2 claws and a gore attack. That's a lot of wiggle-room for design. Form generally follows function. So it's killing mages but not lapping up magical energy from spellbook and scrolls, just suppressing them with its anti-magic field. That's a great hook.

It should have a language or two (Int 10).
I'll add in some description to be a little clearer on what they are, and give them some languages.


And now I'd be curious about the beasts used to hunt them--ooooh a tie-in. Very nice.

The whole reason that this critique is so long is because I really like this critter (probably more than you do :smalltongue: )

Debby

Thaumarite
Size/Type: Medium Magical Beast
Hit Dice: 6d10+12 (45 hp)
Initiative: +0
Speed: 30 ft. (6 squares), fly 120 ft. (average)
Armor Class: 17 (+7 natural), touch 10, flat-footed 17
Base Attack/Grapple: +6/+10
Attack: Gore +10 melee (2d6+4)
Full Attack: Gore +10 melee (2d6+4) and 2 claws +5 melee (1d6+2)
Space/Reach: 5 ft./5 ft.
Special Attacks: None
Special Qualities: Magic Sense, Wise Linguist
Saves: Fort +7, Ref +7, Will +2
Abilities: Str 19, Dex 10, Con 15, Int 10, Wis 15, Cha 15
Skills: Intimidate +6, Listen +9, Spot +3
Feats: Alertness, Flyby Attack, Power Attack
Environment: Grassy Plains
Organization: Solitary or Pair
Challenge Rating: 5
Treasure: Standard
Alignment: Any
Advancement: 7-9 HD (Medium)*
Level Adjustment: -

*A thaumarite that eats a spellcaster becomes a little larger and stronger, gaining a hit die, but also is driven slowly insane, permanently losing one point of wisdom and charisma. A thaumarite that eats four spellcasters becomes a thaumavore with 10 hit dice. However, thaumarites don't willingly eat spellcasters.

Thaumarites speak any four languages, usually common and other humanoid languages such as elven, dwarven and orc.

Thaumarites have large horns on their heads, and look like strange, flying horned dogs. They use their magic sense to evade magic users and have to be trained specially to hunt them down instead of running away from them.

Magic Sense (Ex): A thaumarite instinctively knows the location of each spell, power, caster or manifester within 240 feet, even if the thaumarite doesn't have line of effect to that creature.

Wise Linguist: Thaumarites make up for their lack of intelligence by learning languages based on wisdom, not intelligence.



A lot of that was calculated on the fly. Yeah, thaumarites are actually in some ways better than thaumavores, but that's to be expected.

[Debihuman]

No opinions on the Leimites Debi? YAY I got off; stupid-free!

Not so fast Hot Shot. I just didn't get around to you. And don't feel bad if your design isn't perfect, I hope I can help make it better.

These are vermin and so use Vermin Type and Swarm subtype. Vermin use Cleric BAB. Swarms don't grapple.

Rhinoceros beetles and mantises aren't that dextrous. Dex 30 is too high for them as a locust swarm has Dex of of 22 and this swarm should be less than that. Also, this should have Natural armor like the rhinoceros beetle. I fixed this in the stat block below. AC = 10 + size modifier, Dex modifier and natural armor bonus. Touch is without its armor, and flat-foot is without its Dexterity bonus.

These would fly slower than a locust swarm because rhinoceros beetles don't fly but you could give them better maneuverability than a locust swarm.

Also, rhinoceros beetles have horns for attacking. Why shouldn't these have a normal swarm attack and magic devouring? Don't hamstring your own design.

Blindsense is the ability to sense physical things when you can't see them, it doesn't mean you can sense magic auras. It is also missing a range. I think you should rename the ability magic sense. Blindsense isn't really needed because you forgot vermin have darkvision 60 ft.

Devouring magic items -- cool effect. Now let's look at it from an ecological perspective. I gave them an actual preference for magical items. No save because this ability should have teeth! (Bad pun I know). Also, it's too stupid to know the cheap potion or cheap scroll the PCs dropped for it to devour is so they can run away with their better magic items intact.

Bonus hit points should be temporary hit points.

Rather than put you through the hoops, I've made a new stat block with all my recommended adjustments below. Note: Nystul is not open content so use magic aura as the open content version of the spell.

Leimite Swarm
Tiny Magical Beast (Swarm)
Hit Dice: 7d8-7 (24 hp)
Initiative: +5
Speed: 10 ft. (2 squares), fly 20 ft. (average)
Armor Class: 22 (+5 Dex, +2 size, +5 natural), touch 17, flat-footed 17
Base Attack/Grapple: +3/—
Attack: Swarm (2d6 and magic devouring)
Full Attack: Swarm (2d6 and magic devouring)
Space/Reach: 10 ft./0 ft.
Special Attacks: Distraction, magic devouring
Special Qualities: Darkvison 60 ft., dimensional drag, half damage from slashing and piercing, immunity to to all mind-affecting effects (charms, compulsions, phantasms, patterns, and morale effects, magic absorption, magic sense, mindless
Saves: Fort +1, Ref +12, Will +8
Abilities: Str 1, Dex 20, Con 8, Int -, Wis 17, Cha 2
Skills: —
Feats: —
Environment: Any
Organization: Solitary, force(2-7 swarms), or devastation (11-20 swarms)
Challenge Rating: 4
Treasure: None
Alignment: Neutral
Advancement: None

An undulating cloud of speckled, slightly luminous insects; halfway between a mantis and a rhinoceros beetle, bears down on the area.

A leimite swarm seeks to devour any and all magic it encounters. The swarm deals damage to magic casters and magical equipment being used.

Distraction (Ex): Any living creature that begins its turn with a leimite swarm in its space must succeed on a DC 12 Fortitude save or be nauseated for 1 round. The save DC is Constitution-based.

Dimensional Drag (Su): Any spell that teleports a creature from within 30 feet of a leimite swarm automatically takes the swarm with it, regardless of the limitations of the magic in question.

Magic Absorption (Su): A leimite swarm is immune to magic of all kinds. Any magical or psionic effect that touches a leimite swarm grants the swarm 2 hit points per spell level. Excess healing above its base hit points is treated as temporary hit points. These temporary hit points are the first to be lost when taking damage and any excess fades 1 hour after the last time damage was taken. No magical effect can prevent this; even antimagic fields are not immune. Weapons with a magical enhancement, heal the swarm by their magical enhancement per attack (i.e. a medium sized +2 warhammer deals 1d8+2-2 damage before adding user strength modifier).

Magic Devouring (Su): Every round every creature within the space of a leimite swarm that is capable of casting spells, using spell-like abilities, and using psionic powers takes 1 point of ability damage. This ability damage targets the creature's main casting statistic. In addition, a leimite swarm is capable of devouring magic items, ignoring hardness and magical deflection bonuses. Intelligent magic items are always targeted first, losing 1 ability point each round until it has none and is consumed. Unintelligent magic items can be devoured as a standard action, though they seem to prefer potions and scrolls to other magical items.

Magic Sense (Ex): Leimite swarms sense magical auras (even those disguised by a magic aura spell) within 30 feet. A swarm will ignore all living creatures that do not possess such an aura unless they are carrying magical items the swarm likes to devour.

Debby

[AtlasSniperman]

Not so fast Hot Shot. I just didn't get around to you. And don't feel bad if your design isn't perfect, I hope I can help make it better.
OH no! You mean I'll be getting advice on how to make creatures in the future? WHATEVER SHALL I DO?

These are vermin and so use Vermin Type and Swarm subtype. Vermin use Cleric BAB. Swarms don't grapple.
You say that, but then keep them as Magical Beast in your stat block?

Rhinoceros beetles and mantises aren't that dextrous. Dex 30 is too high for them as a locust swarm has Dex of of 22 and this swarm should be less than that. Also, this should have Natural armor like the rhinoceros beetle. I fixed this in the stat block below. AC = 10 + size modifier, Dex modifier and natural armor bonus. Touch is without its armor, and flat-foot is without its Dexterity bonus.
It was meant to be a visual approximation. The original working idea was aberrations that were actually magic themselves, but I dropped that and went to Magical beast. Though I do like your changed stats in this regard, they do make a lot of sense.

These would fly slower than a locust swarm because rhinoceros beetles don't fly but you could give them better maneuverability than a locust swarm.
Fair cop given the train of thought.

Also, rhinoceros beetles have horns for attacking. Why shouldn't these have a normal swarm attack and magic devouring? Don't hamstring your own design.
The idea is that they are arcanavorous. I.e. they don't give a rats about non-magical things. But the point that they have horns; why shouldn't they attack, is quite valid.

Blindsense is the ability to sense physical things when you can't see them, it doesn't mean you can sense magic auras. It is also missing a range. I think you should rename the ability magic sense. Blindsense isn't really needed because you forgot vermin have darkvision 60 ft.
I was going to explain why I used Blindsense and what I meant by it, but it's clear you understand that, and I'm happy for the correction.

Devouring magic items -- cool effect. Now let's look at it from an ecological perspective. I gave them an actual preference for magical items. No save because this ability should have teeth! (Bad pun I know). Also, it's too stupid to know the cheap potion or cheap scroll the PCs dropped for it to devour is so they can run away with their better magic items intact.
Another reasonable point, though I have 2 problems with your version of the ability. Firstly "capable of casting spells, using spell-like abilities, and using psionic powers" Due to the existance of some people, I would personally recommend changing 'and' to 'or' so instead of meaning they have to use all those abilities, it means they have to use any one or more. The other is; The idea was that when dealing with magic weapons, the enhancement heals rather than harms. So instead of "i.e. a medium sized +2 warhammer deals 1d8+2-2 damage before adding user strength modifier" I was meaning "i.e. a medium sized +2 warhammer deals 1d8-2 damage instead of 1d8+2 before adding user strength modifier" Though I can see how that would be ambiguous.

Bonus hit points should be temporary hit points.
Right, thanks. I was considering having it so if the swarm ends up with temporary hit points equal to its base hit points, it splits into two swarms of full base hit points and no temporary hit points. But figured that would be a bit too extreme.

Rather than put you through the hoops, I've made a new stat block with all my recommended adjustments below. Note: Nystul is not open content so use magic aura as the open content version of the spell.

Leimite Swarm
Tiny Magical Beast (Swarm)
Hit Dice: 7d8-7 (24 hp)
Initiative: +5
Speed: 10 ft. (2 squares), fly 20 ft. (average)
Armor Class: 22 (+5 Dex, +2 size, +5 natural), touch 17, flat-footed 17
Base Attack/Grapple: +3/—
Attack: Swarm (2d6 and magic devouring)
Full Attack: Swarm (2d6 and magic devouring)
Space/Reach: 10 ft./0 ft.
Special Attacks: Distraction, magic devouring
Special Qualities: Darkvison 60 ft., dimensional drag, half damage from slashing and piercing, immunity to to all mind-affecting effects (charms, compulsions, phantasms, patterns, and morale effects, magic absorption, magic sense, mindless
Saves: Fort +1, Ref +12, Will +8
Abilities: Str 1, Dex 20, Con 8, Int -, Wis 17, Cha 2
Skills: —
Feats: —
Environment: Any
Organization: Solitary, force(2-7 swarms), or devastation (11-20 swarms)
Challenge Rating: 4
Treasure: None
Alignment: Neutral
Advancement: None

An undulating cloud of speckled, slightly luminous insects; halfway between a mantis and a rhinoceros beetle, bears down on the area.

A leimite swarm seeks to devour any and all magic it encounters. The swarm deals damage to magic casters and magical equipment being used.

Distraction (Ex): Any living creature that begins its turn with a leimite swarm in its space must succeed on a DC 12 Fortitude save or be nauseated for 1 round. The save DC is Constitution-based.

Dimensional Drag (Su): Any spell that teleports a creature from within 30 feet of a leimite swarm automatically takes the swarm with it, regardless of the limitations of the magic in question.

Magic Absorption (Su): A leimite swarm is immune to magic of all kinds. Any magical or psionic effect that touches a leimite swarm grants the swarm 2 hit points per spell level. Excess healing above its base hit points is treated as temporary hit points. These temporary hit points are the first to be lost when taking damage and any excess fades 1 hour after the last time damage was taken. No magical effect can prevent this; even antimagic fields are not immune. Weapons with a magical enhancement, heal the swarm by their magical enhancement per attack (i.e. a medium sized +2 warhammer deals 1d8+2-2 damage before adding user strength modifier).

Magic Devouring (Su): Every round every creature within the space of a leimite swarm that is capable of casting spells, using spell-like abilities, and using psionic powers takes 1 point of ability damage. This ability damage targets the creature's main casting statistic. In addition, a leimite swarm is capable of devouring magic items, ignoring hardness and magical deflection bonuses. Intelligent magic items are always targeted first, losing 1 ability point each round until it has none and is consumed. Unintelligent magic items can be devoured as a standard action, though they seem to prefer potions and scrolls to other magical items.

Magic Sense (Ex): Leimite swarms sense magical auras (even those disguised by a magic aura spell) within 30 feet. A swarm will ignore all living creatures that do not possess such an aura unless they are carrying magical items the swarm likes to devour.

Debby
Thank you Debby for another very comprehensive explaination of where my doofs are. I intend to learn from this in future :)

[Gelscressor]

While they are not perfect, nishruu might also be of interest. They are listed in Monsters of Faerun/Lost Empires of Faerun.

Abilities include, but are not limited to:
- Spells that normally deal hit point damage instead give permanent bonus hp equal to the amount they would have otherwise dealt
- Non-damaging spells give 1 HP per spell level bonus hp
- Magic items in contact are drained 1d4 charges per round
- Magic item effect negation while there is contact
- Spell Draining combined with risk of being feebleminded on a failed save.

[BladeofObliviom]

MMIII has the Arcane Ooze, which is definitely intended to be a mage-killer. It has golem-style Magic Immunity, though unlike a golem all of the specific exceptions to this ability are actually strengths rather than weaknesses. Namely, both lightning and acid damage bring active benefits to it. It has a passive aura that requires any arcane spellcaster starting their turn within 60 feet of it to make a (very high DC relative to monster CR) Fort save or lose a random one of their highest-level spell slots, and the monster gets temporary HP off of it to boot.

It's also built to grapple; it has improved grab, constrict, and bonus acid damage on its slam and constrict attacks. It has blindsight and is found in underground environments where the 60 ft. range limitation is unlikely to be an issue. It has a large racial bonus to climb checks and its description text seems to imply that it attacks from ambush whenever possible.

Obviously there are ways for a well-prepared or lucky wizard to deal with such a creature, but it's still a nasty contender at CR 9, especially if the fight gets prolonged for whatever reason and it eats a lot of spells. I don't know what kind of threat level you're hoping for but this thing isn't bad at all.

[Debihuman]

If you don't mind officially licensed products, Towers of Sorcery for the Dragonlance setting has a thaumavore (sorta eel-like) but I really like the way they handled the magical draining special ability. I think the save makes sense and that drained levels should return quicker than actual draining as it's not bestowing negative levels. I took the liberty of updating the ability here:


Magebane (Ex): Thaumavores feed on magical energy, much like a rod of absorption. To use this ability, a thaumavore must strike a target . If it succeeds, it deals damage and may drain 1d3 caster levels from the target, or from magic items carried by the target if the target is not an arcane spellcaster. The target is allowed a DC 15 Will save to negate this effect (including trying to prevent an item from being drained). A spellcaster who loses caster levels to a thaumavore’s magic drain loses any prepared spells that he can no longer cast, and his effective caster level for purposes of spells per day, spell variables, and other effects is reduced by the amount drained. Items that are drained similarly lose any level-dependent effects, and if all caster levels are drained the item is rendered inactive. The save DC is Charisma-based. Caster levels drained from spellcasters return at a rate of 1 per hour. For example, a 10th level wizard who is reduced to an effective caster level of 3 by a thaumavore’s magic drain will recover completely in 7 hours. Caster levels drained from items return at a similar rate. A magic item’s qualities, if not level-dependent, are restored as soon as at least 1 hour has passed. A thaumavore can drain no more than double its HD in caster levels in total per day before it is satiated.

Lemme know what you think. My only concern is that the AMF that surrounds the thaumavore would actually interfere with its feeding and draining. I think you might want to reconsider that ability. It should be able to suppress that ability to feed.

As for the changes to the Leimite Swarm, I used the Vermin as a jumping off points, and should have just noted that they are in fact magical beasts. That was my Doh! moment :smallredface:
Debby

P.S. Thaumavore has 26 skill points to use so its skills are off.

P.P.S. Since you never gave them an ecology I decided to muck about with the design. Here's my comprehensive version of the thaumavore


Thaumavore
Large Magical Beast
Hit Dice: 10d10+30 (85 hp)
Initiative: +0
Speed: 30 ft. (6 squares), fly 60 ft. (poor)
Armor Class: 20 (-1 size, +11 natural), touch 9, flat-footed 20
Base Attack/Grapple: +10/+20
Attack: Gore +15 melee (2d6+6)
Full Attack: Gore +15 melee (2d6+6) and 2 claws +10 melee (1d6+3)
Space/Reach: 10 ft./5 ft.
Special Attacks: Magebane
Special Qualities: Antimagic Field, Darkvision 60 ft., Low-Light Vision, Magic Sense
Saves: Fort +10, Ref +7, Will +3
Abilities: Str 23, Dex 10, Con 17, Int 10, Wis 11, Cha 11
Skills: Intimidate +11, Listen +6, Move Silently+7, Spot +6
Feats: Alertness, Cleave, Flyby Attack, Power Attack
Environment: Anywhere there a source of magic, usually temperate plains
Organization: Solitary
Challenge Rating: 7
Treasure: Standard
Alignment: Always neutral
Advancement: 11-15 HD (Large); 16-30 HD (Huge)
Level Adjustment: —

Thaumavores are creatures who have grown used to the taste of magi, often growing from the great beasts used to hunt them, into a creature that does nothing but prey on magic-users.

Thaumavores resemble large black-horned black wolves with batlike wings. These nocturnal predators stake out an area of where magic is likely to be used in order to feed. A thaumavore uses it its horn to sense magic and to attack.

They tend to live near places that radiate magic—especially any place with a magical pool where they can drink without any adverse reaction to the environment and still feed off the magical property. They cannot drain a magic pool as the water refreshes constantly. While they are solitary creatures, their territories tend to overlap so that the scarce resources can be shared without conflict and pups can be raised in relative safety.

On rare occasions, thaumavores will form temporary packs to hunt black dragons, who they despise for their water corrupting ability. After a successful kill, thaumavores will feast on dragon flesh until they’ve picked the carcass clean. The skulls of such dragons are often kept as trophies by the thaumavore that dealt the killing blow.

Thaumavores cannot speak but most understand either Common or Sylvan.

Antimagic Field (Ex): A thaumavore constantly radiates an antimagic field; only the area has a 20 foot radius. It can suppress this ability as a free action, which it does when it uses its magebane ability to feed.

Magebane (Ex): Thaumavores feed on magical energy, much like a rod of absorption. To use this ability, a thaumavore must strike a target. If it succeeds, it deals damage and may drain 1d3 caster levels from the target, or from magic items carried by the target if the target is not an arcane spellcaster. The target is allowed a DC 15 Will save to negate this effect (including trying to prevent an item from being drained). A spellcaster who loses caster levels to a thaumavore’s magic drain loses any prepared spells that he can no longer cast, and his effective caster level for purposes of spells per day, spell variables, and other effects is reduced by the amount drained. Items that are drained similarly lose any level-dependent effects, and if all caster levels are drained, the item is rendered inactive. The save DC is Charisma-based. Caster levels drained from spellcasters return at a rate of 1 per hour. For example, a 10th level wizard who is reduced to an effective caster level of 3 by a thaumavore’s magic drain will recover completely in 7 hours. Caster levels drained from items return at a similar rate. A magic item’s qualities, if not level-dependent, are restored as soon as at least 1 hour has passed. A thaumavore can drain no more than double its HD in caster levels in total per day before it is satiated.

Magic Sense (Ex): A thaumavore instinctively knows the location of each magic item, psionic item, spell, power, caster, and manifester within 120 feet, even if the thaumavore doesn't have line of effect to that creature.

[arkangel111]

Sorry I left this thread hanging. I got busy IRL and honestly forgot I even posted this thread. I like the ideas posted, especially the swarm. The Thaumavore is interesting as well but i'd have to tweak it for my needs. A talking animal is anathema to the group making it so I'd lower the int significantly.
I really like the ideas presented though and will be borrowing them. one small, well lets face it huge change to my setting is that I was introduced to spheres of power and like it a lot. how would you suggest altering the creature abilities to accomodate for the changed type of casting?
Drain spell points and suppress the basic casting ability?

sorry this thread went unanswered for so long lots of things happened and my mind was far from my fantasy life.