D&D 5E As a DM, what monster abilities do you find difficult to run?

[Stalker0]

Sometimes, a thing that looks perfectly good or innocent on paper, actually becomes quite annoying for a human DM to manage in an actual combat. So what monster abilities do you find that are actually very difficult for you to run as the DM.

I'll start off with:

Reactions
In general, I find reaction abilities are so easy to forget as a DM when I'm running a combat with a number of monsters (aka most combats). I already have a ton of things to keep track of on my turns, let alone thinking about having to react to players turns!

With legendary monsters, they are special enough that its usually ok, but I tend to dislike reactions on normal monsters.

Parry
While I dislike reactions in general, I forget about Parry all the time.

Beyond just the normal forgetfulness of reactions, in order to keep my large combats moving quickly, my players will often roll their attacks ahead of time, especially when they have summons and the like. But that means temporary AC bonuses get muddied, and again makes it even easier for me to forget. But I WANT my players to do that, it makes the combat go so much quicker.... so the reality of speedier combat interferes with the one paper theory of what the monster should do.

 

[Istbor]

Recently, I have been forgetting about Regeneration in some monsters.

I have lucked out, that the fights are still pretty challenging, but when I have looked back I have a real face-palm moment.

 

[Galendril]

Spell-casting. Any spell list over 10 long is too much to manage. Usually, fights are over so quickly the caster can only get one or two spells off anyway.

 

[Laurefindel]

Spellcasting for me too.

It isn’t hard to use per se, but I find it difficult to use NPC magic efficiently without me spending some serious time before the battle to come with anything that resemble a strategy that the creatures would likely have with access to those spells.

 

[WayOfTheFourElements]

I have a hard time getting the most out of monsters' movement abilities.

 

[ART!]

Yup: spellcasting!

I've got enough to keep track of without all that fruffery. I've run 5E enough now that I tend to just look at their list of spells and come up with a few quick-and-dirty features that emulate the more useful ones. 9 yards and a cloud of dust.

 

[DND_Reborn]

I don't have any issue with spellcasting except it takes a bit of time deciding what to cast--especially for high-level casters.

The thing I forgot the most in the past was Legendary Actions. They are listed at the end of most creatures and I have to remind myself to double-check, especially if I am running multiple monsters (some with them and some without).

I wish they were put ahead in the stat block so they were a bit more prominent. Of course, I don't have as much trouble with them now as I did at first. shrug

 

[iserith]

Spellcasting. Though it's not too bad since I run on Roll20 and it's easier to view spell details than flipping through a book. Still, I'd much prefer spell-like actions in the statblock a la D&D 4e, particularly as the spellcasting monster/NPC isn't likely to get many spells off before buying the farm.

 

[Charlaquin]

Another one for spellcasting. I don’t remember off the top of my head what every spell does, and I don’t want to have to choose which spell to cast from a big honking list every time. Just give the monster two or three abilities that replicate the effects of spells you want them to cast and give them each recharge 4-5 or whatever. Or heck, give it a number of uses per day if you want, but put all that stuff about it being an Xth-level caster and the full spell list in the notes and leave them out of the stat block, please!

 

[J-H]

Spellcasting. I put summaries in my spell list, ie:
Hold Person (C, 1 target, wis or paralyze, upcast +1/lvl), Fireball (150', 20' radius, 8d6 fire, Dex half)
It helps a lot to have pre-done tactics for the casters listing 1-3 top choices for each round of combat & who they will target.