Mordekaiser, Iron Revenant

Menace
When Mordekaiser, Iron Revenant, enters the battlefield each player chooses a creature they
control then sacrifices the rest.
When Mordekaiser, Iron Revenant attacks, exile
target creature from a graveyard. Until end of
turn Mordekaiser, Iron Revenant gains +X/+X
where X is the power of target creature. Lose life
equal to its converted mana cost.