Sung Jin-Woo, S-Necromancer

Whenever a creature you don't control dies, you
get an experience counter.
Sung Jin-Woo, the S-Rank necro gain +1/+1 for
each experience counter you have.
Remove 1 experience counter: target creature you
control fight a creature you don't control.
Remove X experience counter you have: return
target creature with a converted mana cost X into
the battlefield from a graveyard.