Custom Legendary Creature: How did I do?

[eugee]

I'm running an old BECMI adventure in my 5E campaign--X12 Skarda's Mirror. Early in the adventure my group of 5 level 6 players will find themselves in a 5 story tower with dozens of chambers, most of which contain a large panel of mirror propped somewhere in the room. There is a creature in the adventure known as a Mirror Fiend, which I've tried to make into a challenging solo creature for the party to deal with. Normally when there is a BECMI monster with no equivalent 5E monster I just reskin something similar, but for this fight I tried making one from scratch. My goal is something frustrating challenge, but not a TPK. How did I do?

https://puu.sh/GXm6e/1fc39a7a90.png

[Magicspook]

I like it, although it is unclear whether this guy is always inside a mirror or sometimes inside a mirror, and what this means for his attacks.

I think the 8d6 sneak attack damage is a little too much, you can easily murderise a player if you accidentally roll too high. Then again I don't know your players' party composition.

[MrStabby]

It looks cool, actual difficulty will depend on where the mirrors are positioned. If they are easy to get to AND if the party knows about the monster then the encounter will be a LOT easier than if there are mirrors on the ceiling or if there is a mirror unknown at the back of a wardrobe.

That said... be careful with soul sliver - that is a lot of extra damage. At 70 damage per round max throughput this guy is easily chewing through the HP of a level 6 character in one round. Take out the martials first working back through initiative (so focus on the guys where you can move, take an atack as your action and then 3 legendary actions before they get a turn... it could be brutal.

I would also point out that running away is tough - taking an atack of opportunity with a 28 damage boost is nojoke at this level and a 40ft fly speed does make running harder.

I think this could be a bit swingy - possibly too easy but also one mistake on the part of the party and it could snowball into a TPK.

My suggestion (based on theme rather seeing the module) would be to cut the sneak attack damage down by a few D6 and give the demon a bit more magic: mirror image a few times per day, major image (including upcast - use it to create illusiory mirrors to act as traps) or programmed illusion (doesn't matter as its an NPC ability it does what you like), and maybe a once per day fear effect. The aim being to make the setup a bit more "cat and mouse" rather than "combat decided in 2 turns due to large damage on both sides" but also evening things up between your casters and warrior characters (assuming they have magic weapons) and to give casters focussed on save spells a greater liklihood they can do something.

[eugee]

Some good points. To elaborate, the party (celestial warlock, light cleric, ancients paladin, gloomstalker ranger, and swashbuckler rogue) will be aware of a beast that raged through the tower. They will also be aware of a mirror that it came through, although they will think it was a mirror of lifestealing. The mirror fragments throughout the tower are plainly visible in every room, obviously "pieces" of broken mirror. (Which were brought and placed in each room of the tower from a pocket dimension of mirrors by the fiend.) This will be the first combat encounter of the adventure and they will be fresh and full strength.

The puzzle is to figure out you have to break all the mirrors before the fiend defeats them. It's tactic is to shift out of a mirror into the real world and bite, survive one player turn, then flicker out of sight, survive another player turn, then shift into a mirror. If forced to shift into a mirror in front of the players they should have no trouble destroying the mirror it is in. In response to Magicspook, it can move into, out of, for in between nearby mirrors once per round (2 legendary actions). While in a mirror it can just alter appearance in the reflection, no attacks. For example, appearing behind a couch in a mirror's reflection, and when a player investigates, emerge from the mirror and attack. Anytime it emerges it will have to go a full round before it can return to a mirror (since it's 2 legendary actions to Mirror Shift).

I did feel that Soul Sliver (sneak attack) is high but 14 (bite) + 28 (sliver) + 14 (claw), should be it's normal round as it should use Mirror Shift almost every round, that puts the average DPR at ~56 which is CR 10 offense, and it's CR 8 defense. My goal is for this thing to be essentially a very scary rogue. It doesn't have a lot of health for its CR, and while it's hard to hit I expect it to get tagged frequently by the party. You're absolutely right that fleeing it will require Disengage (not for the rogue) or forced movement, but two PCs engaging it will also stop it from being able to sneak attack.

You're right though, this thing could be lethal if my dice are hot. I'll have to think about the Soul Sliver more, especially the mirror image ability--very thematic and would give the creature some more staying power.

[J-H]

Not bad. It's going to probably burn 2/3 Legendary Actions each round teleporting between mirrors though. You may want to let it move between mirrors as part of its move action (consuming something like 5' of movement per 10' of mirror distance teleported).

[MrStabby]

two PCs engaging it will also stop it from being able to sneak attack.


Not quite...

It can move away from one and attack the other that it is still next to. Sure that will take an attack of opportunity, but you have given the ability "flicker" if it wan'ts to avoid that.

So I can see the fighters closing this down, then legendary action it slips past all of them and one shot's the party wizard - saving flicker for the last legendary action before its turn. Even sliver+bite will be doing 42 damage on a hit. A Wizard (unless they rolled well for HP) would need +3 Con and to basically have not taken any damage to not be killed by the average damage roll.


Also - how is round defined? Is a round from highest initiative to lowest, or is it more "since this point in the last cycle"?

[eugee]

Not quite...

It can move away from one and attack the other that it is still next to. Sure that will take an attack of opportunity, but you have given the ability "flicker" if it wan'ts to avoid that.

So I can see the fighters closing this down, then legendary action it slips past all of them and one shot's the party wizard - saving flicker for the last legendary action before its turn. Even sliver+bite will be doing 42 damage on a hit. A Wizard (unless they rolled well for HP) would need +3 Con and to basically have not taken any damage to not be killed by the average damage roll.


Also - how is round defined? Is a round from highest initiative to lowest, or is it more "since this point in the last cycle"?

I'm good with it being slippery via Flicker, but yeah that's a good point, I think the avg HP in the group is 45. So let me tone down the damage output.

I like the bite at 14 (3D6+4), but let's tone down the Sliver a bunch... to 10 (3D6). That essentially makes it a critical bite, though if it actually criticals it will be monstrous (I'm fine with that, 4 of 5 PCs can heal). That's 24 damage, and then 1 Claw by default, but up to 3. Let's say it does 2 claws per round on average, another 28 damage is a tad high... I'll make the Claws do 9 (2d4+4) which puts the DPR at 42 (14 + 10 + 9 + 9). Granted to do that much it has to skip Mirror Shift which will likely mean a ton of return damage.

On the round thing, you're right, with the current wording it would only be able to Flicker from something that has lower initiative. I should change the wording to "... attacked since the start of it's last turn."

In order to be CR9 still, I think it needs something defensively, and I like mirror image. What about casting Mirror Image as a reaction to being looked at, with recharge 6, while outside of a mirror (spell ends if it shifts into a mirror). That would allow it to stay out of a mirror for a round without losing half its hit points. Or to make it simpler, cast as a reaction if within 60' of a 1'x1' mirror in the real world.

Revised Block:

https://puu.sh/GXtvJ/89091302e6.png

[J-H]

How about Blur instead of Mirror Image? Easier to adjudicate, and Blur goes down if the party breaks its Concentration.

[eugee]

Not bad. It's going to probably burn 2/3 Legendary Actions each round teleporting between mirrors though. You may want to let it move between mirrors as part of its move action (consuming something like 5' of movement per 10' of mirror distance teleported).

You're right--I was looking to handle all mirror movement with one entry. I'll instead move the jumping from mirror to mirror under Manipulate Reflections as a reaction. Then it can move between mirrors once per turn, and reserve the legendary action for entering or leaving mirrors.

https://puu.sh/GXu2i/5f3837ef40.png

[eugee]

How about Blur instead of Mirror Image? Easier to adjudicate, and Blur goes down if the party breaks its Concentration.

Hmmm. Disadvantage would certainly make it harder to hit, though concentration makes it a liability. Mirror Image equals wasted attacks, and thematically is more appealing to me. As the paladin and ranger will realistically burn through three images in one turn (both dual wield), and the warlock & rogue can easily knock out two, it's probably a wash mechanically. I think I'm going to stick with Mirror Image only for the description.

[Magicspook]

Sounds like a fun encounter!

[MrStabby]

You're right--I was looking to handle all mirror movement with one entry. I'll instead move the jumping from mirror to mirror under Manipulate Reflections as a reaction. Then it can move between mirrors once per turn, and reserve the legendary action for entering or leaving mirrors.

https://puu.sh/GXu2i/5f3837ef40.png

Looks like a fun encounter - still potentially very tough and quite swingy, but I think its fair.

One ability I would add... is the ability to look out of any reflective surface within 500ft. The ability to spy on the party and to know whats going on just means it can protect its mirrors a bit better - it won't be chilling in one mirror and the party gets to smash the others without it realising what they are doing.

[Dr. Cliché]

Just an idea - instead of going with the standard Legendary Resistance, what about something like this:

Reflected Soul
Whenever the Mirror Fiend fails a saving throw, it may choose to succeed it instead. If it does, a random mirror within 60ft* is destroyed. The Mirror Fiend cannot use this ability if there are no unbroken mirrors within 60ft.

*60ft is an arbitrary value - use whatever is appropriate for your encounter.

Up to you, of course, but I thought this might be a little more flavourful than the standard Legendary Resistance. However, I'll freely admit that I'm biased here as I consider Legendary Resistance to be terrible game design and one of the worst things to come out of 5th edition. :smalltongue:


Regardless, I really like the idea behind this creature and I think you've done a great job. Kudos.

[eugee]

Just an idea - instead of going with the standard Legendary Resistance, what about something like this:

Reflected Soul
Whenever the Mirror Fiend fails a saving throw, it may choose to succeed it instead. If it does, a random mirror within 60ft* is destroyed. The Mirror Fiend cannot use this ability if there are no unbroken mirrors within 60ft.

*60ft is an arbitrary value - use whatever is appropriate for your encounter.

Up to you, of course, but I thought this might be a little more flavourful than the standard Legendary Resistance. However, I'll freely admit that I'm biased here as I consider Legendary Resistance to be terrible game design and one of the worst things to come out of 5th edition. :smalltongue:


Regardless, I really like the idea behind this creature and I think you've done a great job. Kudos.


DUDE. I love that! Thematically, it's awesome--and a clue to start smashing mirrors! Mechanically, he'll probably get MORE than 3 uses, as well, since in this scenario there are 5 floors with roughly a dozen mirrors placed per floor (which is 50'x50'). I think it needs to be the NEAREST mirror within 60' (which is a good distance that every other power is restricted to). So by giving up it's closest escape route it can shrug off a failed save.

[Asisreo1]

I feel the sliver is getting a bit of undeserved flack if I'm reading the statblock correctly.

It must have advantage on the roll before getting the extra damage, yes? If so, it will probably only get it once in a combat since it doesn't appear to have any feature that grants it advantage natively. The closest thing is Stealth proficiency but I don't think that always is taken into account.

[MrStabby]

I feel the sliver is getting a bit of undeserved flack if I'm reading the statblock correctly.

It must have advantage on the roll before getting the extra damage, yes? If so, it will probably only get it once in a combat since it doesn't appear to have any feature that grants it advantage natively. The closest thing is Stealth proficiency but I don't think that always is taken into account.

No, it also works if there is no creature other than the target within 5ft of the fiend.

And the fiend can move - either normally, or as a legendary action, such that it can stand both next to the target but away from thier supporting PCs.

[Asisreo1]

No, it also works if there is no creature other than the target within 5ft of the fiend.

And the fiend can move - either normally, or as a legendary action, such that it can stand both next to the target but away from thier supporting PCs.
That it is. I somehow looked over that part. I should get new glasses, it seems.

[eugee]

Here is the final stat block that was used in the adventure:

https://puu.sh/H03Ne/194a251397.png

So far it's been very slippery, and nailed the warlock pretty hard. Unfortunately the warlock whacked it with booming blade, and discovered the vulnerability to thunder damage, so the mirror fiend is not long for this world. After four rounds of combat we stopped the session (we ran waaay over), and all of them are speculating the monster right now in our group chat.

They've reasoned out that it can't leave and enter a mirror in the same turn, and know it can move or swipe as legendary actions. They've also witnessed the mirror image, reasoned it's sneak attack is when it's sole engaged, plus figured out that it can't leave a covered mirror. They haven't figured out that it can jump into any mirror within 60' even if it can't see it, but they have determined that the paladin can sense the mirror it is in. Lots of compliments on the creature and excitement over something they've never seen before. Thanks everyone for helping with drawing this thing up!