Vern, Last Man Standing

At the beginning of your upkeep, if you have zero
or less life, no cards in your library, ten or more
poison counters or have been dealt 21 or more
combat damage by a single commander, you win
the game.
At the beginning of your end step, you may
choose up to one target creature. Until your next
turn that creature attacks each combat if able and attacks you if able.