Xindara

Eminence — If Xindara is in the command zone
or on the battlefield, if a player has 20 or more
poison counters, they lose the game. If Xindara
would move into a zone other than the battlefield
or the command zone, return it to the command
zone instead.
Infect
When Xindara enters the battlefield, each player
gets a poison counter, then put a +1/+1 counter
on Xindara for each poison counter among
players.