YEAH WELL THAT MAY BE SO BUT HOW ABOUT THE TIME WHEN YOU...?
Doesn't counter. You take full damage, but upon impact you spontaneously cast a spell back starting with the same letter as the incoming spell, because yeah well my memory may be foggy but remember that camping trip yeah you do and remember that money I said you could keep and...
Doesn't matter if you can't cast spells, a spell will fire off anyway, because retaliating isn't about details, it's about having the last word! Yeah it is! Is too! Yeah well that may be so but how about the time...
YEAH I HEARD YOU THE FIRST TIME!
First time it is cast, it doesn't actually counter the incoming spell - you just face that damage full on.
But if you're targeted a second time with the same spell, you only take half damage, because yeah I like heard you the first time dimwit, like, oh my lord, are you a broken record or just a broken soul?
And if you're targeted a third time, only a third, and so on.
Additionally, after the first time, roll a d6. On a 6, the incoming spell splits and bounces back and does the same damage amount as it just did to you (half, third etc.), like WHY DO YOU KEEP REPEATING THIS I SAID I HEARD YOU THE FIRST TIME LIKE OH MY GOD CALL SOMEONE.