Hey, guys!
I've been playing through Revelations again and got both Counter and Countermagic on my Avatar. I got to the boss without too many problems (Hana be praised) and placed my Avatar directly in front of her. She attacked my Avatar magically for 20 damage, triggering Countermagic, which suddenly did 40 in return, killing her.
My question is: Do Countermagic and Counter stack? Or was it some kind of glitch?