i used a combo that took me like 4 turns to pull off:
charge(2 charge badges)+4 atk
charge again:+4 atk
power lift:+3 atk
power punch:+2 atk
total increase:+13 atk
power plus badge x2:+2 atk
15 atk total
spring jump +16 damage
bob-ombast +10 damage
+15 increases=spring jump +46 atk
+15 increases=bob-ombast +25 atk
kills him on the 5th turn in just one blow from each character.
To all of those poor unlucky souls out there, this is for you:
If you don't watch Black Cat then Train Heartnet has a message for you:
I came to deliver some bad luck.