Polemos, the Massacre

Vigilance, Double strike
On your upkeep, if you do not control a Death
God creature, choose a Death God you control. It becomes a 6/6 creature until
the beginning of your next turn.
If Polemos would be put into the graveyard or
exile from the battlefield, you may instead exile
it. If you do, return it to the battlefield at the end
of the next step.
When Polemos enters the battlefield, goad all creatures.