Star Platinum

Star Platinum can only attack if Jotaro Kujo, Stand User is on the battlefield.
Star Platinum enters the battlefield with X echo counters on it. You don't lose the game for having 0 or less life.
At the beginning of your upkeep, sacrifice Star Platinum if there are no echo counters on it. Otherwise, the target opponent may choose that for each 1 damage that would be dealt with you
until your next upkeep, you remove an echo counter from Star Platinum instead.