Thanos, Mad Titan

Flying, trample
Whenever one or more opponents each lose
exactly 1 life, put a +1/+1 counter on Thanos,
Mad Titan. Exile the top card of your library.
Until your next end step, you may play that card.
"Dread it. Run from it...Destiny arrives, all the
same. And now, it's here. Or should I say...I am."
—Thanos