So what, you assume that the players know all of the monsters' abilities and, what, check them off when they're used?
depends on the table. at yours? probably not.
but i'm currently at a table (well, "table" - it's on roll20) where the DM posts enemy abilities and their usage rate as the ability is used. at that table, yeah, i can absolutely track how many uses of a given ability an enemy has. i'm sure there are also DMs that hint at how many uses enemies have of various abilities via narrative descriptions.
Look, I personally know the monsters quite well.
and at all the tables i've been at, i've never been able to, since every enemy has either been completely custom or else so reskinned as to be practically unrecognizable.
When I'm a player, I turn that part of my brain off. I don't meta-game.
who's been talking about metagaming?
Nor do I assume that the monster is being used exactly the way they are written in the book. And if I knew a monster had LRs, I wouldn't be counting them off, nor would I assume that the DM is using "kiddie gloves" because one didn't get used every time an ability with a save is used. Even if I did know that a particular monster had LRs and knew that they weren't used at that particular moment in time, why would I assume the DM is going soft? Why would you?
because i generally expect enemies to try to win (or at least live)?
And anyway, the monster would have to spend part of their action figuring out exactly what ability the PC used to know if it's worth it to resist--especially in LU where LRs have a side effect to being used. Maybe your millennia-old liches who know every spell would instantly know every spell the PCs could possibly throw at them, but other creatures?
i mean, for one, this also depends on the flow of information at the table. if, for instance, the DM always announces immediately what spell an enemy is going to cast and then allows counterspells from players, that implies that figuring out what spell is going to be cast is easy enough that anyone can do it without a check, so in a game like that, yeah, i'd expect a monster to be able to ration out LRs fairly effectively. but if figuring out what a spell is is difficult, or the legendary enemy is pretty stupid (e.g. a tarrasque)...well, i'd expect them to go pretty quickly. i mean, the enemies want to live, right?
but also, you're assuming legendary resistances are an ability a monster actively chooses to use in-universe, and not just a representation of a monster's increased luck or fortitude. and that's fine, but i doubt there aren't tables that run the other way.
EDIT2: actually, wait, i just realized something. legendary resistance applies after the failed save, i.e. after the spell has been cast and as it's taking effect - why would you need to be able to recognize it to know how dangerous it is at that point? the monster is in the middle of being effected by it, it should be fairly intuitive to determine whether or not it's worth an LR.
Which is fine, but personally I would want them to have to figure it out, rather than just lay it out there in blatantly gamist terms.
oh, im not arguing in favour of one way or the other. im simply arguing there are tables where figuring out an enemy used an LR exist, and that ignoring that at those tables isn't really useful advice.
EDIT: to clarify "ignoring that" as in ignoring it as a player, not as a character. im not advocating in favour of metagaming, i just ran out of time on my break.
