Just a note in case anyone is worried I’m adding a mage to every encounter, I very rarely use counterspell against my players; it’s one of the spells I consider to have high “fun-ruining” potential.
I’m struggling a bit to decide on how to handle this interaction in a way that feels fair. From my understanding RAW, a character doesn’t know what spell is being cast. I think you can use your reaction to make an arcana check to discern it, but of course then you can’t counterspell it. For enemy spellcasters I generally describe what’s being cast, instead of naming the spell right away, but it can slow combat down, and is a bit one-sided since when a player casts a spell they lead with “I cast X”. This leads to an imbalance where I’m aware of what’s needed to counterspell something while the players are not, and can cause some awkwardness trying to decide how to play around that without metagaming.
I can think of a few different ways to handle this, each with its own drawbacks, but I’m curious to hear what y’all do at your tables!
NGL (and I only have dm experience in 3 modules with a handful of players so take with a large grain of himalayan pink salt mmm) - I generally use mages and counterspell specifically to discourage lazy play. Blast the last 4 cultist encounters with fireballs? Oh man is there a counterspell ready caster in the next lol. Midlevel bosses and BBEGs aren’t dumb, they know magic exists, and they’ll retain talent. Letting that talent show illustrates the stakes, as well.
But I don’t use it to counter healing or well role-played hijinks.
Yeah I’m not against using it as a means of tweaking balance in encounters, like if a particular character is trivializing or dominating every encounter with certain spells