Holy shit did I get lucky...
First Turn
I attack him, hit but no Aether. He counters, hit but no Luna. Mist runs up, heals Ike to full.
His turn. He attacks. Hit, but no Luna. Ike counters, Aether!
Second Turn
I attack him. Hit, but no Aether. He counters, hit but no Luna. Must runs up and heals Ike to full.
His turn. He attacks. Hit, but no Luna. Ike counters, Aether! I win!!
I can't believe how insanely lucky I just got. My Skill is nowhere near max, so I'm surprised Aether actually went off those two times.