Hell's Caretaker

Creature - Horror

, Sacrifice a creature: Return target creature card from your graveyard to the battlefield. Activate only during your upkeep.

"The rules are clear. If you want to leave, you need only convince another to take your place."

1/1

2018-03-16 Hell's Caretaker can be the creature sacrificed to activate its ability, but it can't be the target of its own ability.
2018-03-16 The upkeep step is before the draw step, after the untap step. Because the turn has already begun, creatures put onto the battlefield during your upkeep won't be able to attack or pay a {T} cost this turn.

mtg.wtf