Counterspell [reaction] (Feat 1)
Abjuration, Arcane, Wizard
Trigger A creature Casts a Spell that you have prepared.

When a foe Casts a Spell and you can see its manifestations, you can use your own magic to disrupt it. You expend a prepared spell to counter the triggering creature’s casting of that same spell. You lose your spell slot as if you had cast the triggering spell. You then attempt to counteract the triggering spell (page 458).