March of the Blind Compleation

All Eldrazi are Phyrexian.

Whenever you deal lethal damage to a player or a player receives their 10 or more poison counters. You gain control of all of their creatures as a state based action.

When a player loses the game, if you control one or more creatures controlled by that player, you do not have to return those creatures until they either leave the battlefield or you lose/win.