View Full Version : D&D 5e/Next Sword Spider (help/critique)

2018-03-11, 05:45 AM
so this is my first stab at a 5e monster. It's based on the "cutlass spider" pathfinder creature (sorry can't post links yet) but I sort of upped the power level a little bit. It's difficult because the intention isn't really for them to defeat the monster, at least not on their first shot against it. I'm running a west marches style campaign and I really like the idea of a guardian construct that the players either have to sneak past or come back to when they are more powerful. Basically I just want to scare the crap out of them to make them realize theyre going to have to be smart. I know that doesn't always go so great, but I can't shake this vision of a big seemingly indestructible robot stalking the corrodors of a long forgotten wizard tower.

It's worth knowing that this guy's behavior is extremely predictable, walking the same loop through the dungeon over and over and the players can hear his big clanky legs coming and can duck into rooms that he is incapable of fitting in. He only ever ditches the "railed" search pattern if someone uses a gem key to open specific magically locked iron doors and will then take the fastest route to get to that location. There are a few clever ways of defeating it without fighting it, such as throwing a sentient weapon for it to absorb (there is one in the dungeon), capturing a rust monster from another dungeon and bringing it to this one, or answering a riddle it asks as to confirm you are it's user although the riddle is pretty obtuse and is really more there for flavor (think of it as a security question for a password)

Name: Sword Spider
Creature Type: N Large Construct
Proficiency Bonus: +3

AC: 20 (natural armor)
Hit Points: 85 ( 10d10 + 30)
Speed: 40 ft

STR 19 (+4) DEX 14 (+2) CON 16 (+3) INT 7 (-2) WIS 10 (+0) CHA 3 (-4)

Senses: Blindsight 10. Darkvision 60. Passive Perception 11
Damage Resistances: Piercing, Slashing and Bludgeoning
Damage Immunities: Poison
Condition Immunities: Charmed, Exhaustion, Frightened, Paralyzed, Poisoned

Longsword Weapon Arm Attack: Reach 5ft. +7 to hit, (1d8 + 4 slashing damage)
Pike Weapon Arm Attack: Reach 10ft. +7 to hit (1d10 + 4 piercing damage)
Maul Weapon Arm Attack: Reach 5ft. +7 to hit (2d6 + 4 bludgeoning damage)

Multiattack: The Sword Spider makes x (start at 3, maximum 5) attacks with itís weapon arms.

Absorb Weapon:
The sword spider can replace any of itís multiattack attacks against a creature within 5 feet of it with a special disarm maneuver, forcing it to drop one item of the sword spiderís choice that itís holding. The target must make a DC 16 Strength saving throw. On a failed save, it drops the object the sword spider chooses. The weapon can not be retrieved until the Sword Spider is destroyed. If it absorbs a weapon it forms a new leg and gains another weapon arm attack at the end of itís next turn.

Siphon Magic Attack: As a reaction to when the Sword Spider is the target of a ranged spell attack that deals damage, it can grant itself and any allies within the area of effect resistance to the damage. The sword spider is stunned until the beginning of itís next turn. On its next turn the only action it can take is to cast the spell. It is proficient with spells cast through this ability and uses itís dexterity modifier to cast with it (DC 13). It has advantage on ranged spell attacks cast with this ability and creatures have disadvantage on saves against spells cast with this ability. If no creatures are in range, the sword spider discharges the spell at an unoccupied space.

Lair Actions: On initiative count 20 (losing initiative ties), the Sword Spider takes a lair action to cause one of the following effects;

Call 1d4 Automatons from nearest chute
Close Gem Activated Door (locks the door for 1d4 rounds)

Anyways, like I said, this is my first monster in this system and it's really hard to tell what mistakes i've done as far as power balance. Some places i've erred on the side of caution but it's abilities... not so much. I'm really not sure if the absorb weapon ability should be something it can do on top of it's multiattack or not, but I really want to showcase it's main feature.

I'd appreciate that it didn't outright murder the party but I do really want to scare them away from seriously fighting it till like 5th level (and they won't encounter it until theyre at least 3rd). I also wouldn't be hugely upset if they somehow did kill the thing at an early level, it should just be a hard fought battle. I also have no frickin clue what challenge rating this guy is considering his abilities but I was operating under the assumption that it was like 7-ish.

Critiques would be great, thanks.

Morphic tide
2018-03-11, 07:11 AM
I think some kind of variation setup or advancement rule is needed, as the idea behind it has way too much variation to have a singular statblock. One made out of nothing but regular weapons will function very differently from one that has an Artifact or Legendary weapon integrated into it, and ones with large numbers of weapons integrated have more attacks, which buggers the math quite fiercely. For example, one that has a Defender (http://5e.d20srd.org/srd/magicItems/magicItemsAToZ.htm#defender) in it will be able to trade a +3 from attacks to AC, which alters it's defenses and attacks on the fly by a rather considerable amount. A Sword of Sharpness (http://5e.d20srd.org/srd/magicItems/magicItemsAToZ.htm#swordOfSharpness) means all it's Slashing attacks will always deal maximum damage.

For advancement, I'd go with blade count, defining the baseline characteristics but allowing for size overlap at the bottom and top. Then the magic item rarities alter the baseline statistics as bonuses, with appropriate CR increases, having the "rounded out" changes be the assumed baseline of that size of Sword Spider. For instance, a hundred-blade Sword Spider might be high enough CR that the changes for an uncommon magic weapon aren't enough to warrent a CR change, so you then say that all hundred-blade Sword Spiders always have an uncommon or rarer magic weapon in them. Then the outliers and stuff that warrents special rule interactions like the Sword of Slashing maxing out all damage or Dancing swords being either useless or requiring a special added Action get their own additional CR adjustment as the guidelines call for, based on the changes in damage/defense.

This is more a matter of the creature inherently being a problem for 5e, as 5e doesn't do power increases without defined CR changes. A Sword Spider that's gotten ahold of a Vorpal Sword (http://5e.d20srd.org/srd/magicItems/magicItemsAToZ.htm#vorpalSword) is a heck of a lot more problematic than one that has a Trident of Fish Command (http://5e.d20srd.org/srd/magicItems/magicItemsAToZ.htm#tridentOfFishCommand), and the rules should reflect this in some fashion.

You've made this Sword Spider as a specific guardian, which is alright, but there should be ways to have Sword Spiders as normal enemies (and besides that, Lair actions are encounter design, not really monster design, they're in monster entries for brevity's sake and ensuring that the needed stuff is present) and the mechanics behind them don't fit in with 5e very well. Locking the upper limit of the Sword Spider by core item rarity helps a lot with the situation, as does having "templates" for various roles. A Dancing Sword Spider will be a much more appropriate solo fight than a Sword of Slashing one, as it can have ranged attacks and minions/even more attacks built in, but the Sword of Slashing one has more damage (unless the Dancing one gets nearly double attacks) and as such needs to be higher CR.

2018-03-11, 11:20 PM
I agree with the above post