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!
I’ve found Counterspell to be a pretty positive addition to my encounters. It encourages players to watch when enemies use their reactions, or try to bait a reaction. Rather than frustrating, the players have turned it into part of the game.
I’m also kinda meh about the whole arcana check thing. Casters generally have high DPS/versatility. I feel no need for them to be able to horde their spell slots further. When the party is facing an enemy caster, they announce that they’re casting and I tell them if the enemy caster counterspells.