By the powers of greyskull!

Here’s some ideas for new powers (I did search to see if there was lots of this already, apologies if it’s old hat)

Achilles heel - the weak/strong cycle between red, green and blue is reversed

Clone with the Wind - the hero mimics the exact stats and powers of a chosen enemy

Pyrrhic victory - the hero and a randomly selected enemy both instantly perish

Burn the Witch! - the next three heroes on either side that fire off a special catch fire causing damage for X turns

Mutiny! - all the enemy troops stats are added to your team.

Absolute Zero - either team randomly becomes Zero’s current team for three turns!