Zreth, World's End

Flying, Trample, Haste, Infect
When Zreth, World's End enters the battlefield, sacrifice all other creatures you control. Target opponent gets that many infect counters.
If this creature would die, regenerate it.
At the beginning of your upkeep, if you control this creature; you lose the game.
It rose from Hell that day, the devil's skull lodged beneath
its foot... Squashed like an insignificant insect.