Hanzo Shimada

Opponents declare attackers during their upkeep.
Whenever Hanzo Shimada attacks, flip a coin. If
you lose, Hanzo Shimada doesn't deal damage
this combat. If you win, flip another coin. If you
win, Hanzo Shimada gains double strike until end
of turn.
{2}: Roll a d6. Deal that much damage minus 1 to target creature or player.