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’m not sure but I dont think this addresses OP’s concern re if you use your reaction to figure out the spell you cant then use your reaction to counterspell?
Recalling information never requires an action, the check is just there to determine if you know something or not.
right, yes- but if the spell isnt in their spell list do you then allow them to make an arcana (etc) check to see if they can work out what it is, and if the succeed would that qualify as their reaction?
What I mean is that remembering stuff (like what someone casting a fireball looks like) is what 3rd edition would call a Free Action, like talking. You can do it as much as you like (that can reasonably fit into six seconds) at any time during the turn, and it doesn’t take up any resources (like your reaction). Even though you’re rolling a check, it isn’t using part of your turn.
If it did take a reaction to identify a spell as it’s being cast, that would mean that remembering something would take the same about of time and energy as an opportunity attack.