Sheoldred, Whispering One

Swampwalk
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature.
"Endrek orders everyone around, she believes that she
is in charge. As long as she keeps thinking this, I'll
remain in the shadows, watching and guiding her
where I want her to go." -Sheoldred