Ronin

Leadwall- Whenever an opponent loses life from
an effect other than this ability, each other
opponent loses half that much life
Sword Block- Whenever Ronin blocks a creature,
he gets +0/+X until end of turn, where X is the
amount of life target player lost this turn
Sword Core- {7}: Until end of turn, whenever Ronin attacks, defending player loses 4 life
Crew 3
Ronin can be your commander