Calcifer, Vexing Prince

When Calcifer, Vexing Prince enters
the battlefield, create a 4/3 Vexing Devil.
Whenever a non-token devil creature enters
the battlefield, create a 4/3 Vexing Devil
token with "When Vexing Devil enters the battlefield, any opponent may have
it deal 4 damage to him or her.
If a player does, sacrifice Vexing Devil.
"I am told that Im quite vexing."
-Calcifer, Vexing Prince