Bloodghast

Bloodghast can't block.
Bloodghast has haste as long as an opponent has 10 or less life.
Landfall — Whenever a land you control enters, you may return Bloodghast from your graveyard to the battlefield.

Despoiler of Souls

Despoiler of Souls can't block.
{B}{B}, Exile two other creature cards from your graveyard: Return Despoiler of Souls from your graveyard to the battlefield.

Gutterbones

Gutterbones enters tapped.
{1}{B}: Return Gutterbones from your graveyard to your hand. Activate only during your turn and only if an opponent lost life this turn.

Nether Spirit

At the beginning of your upkeep, if Nether Spirit is the only creature card in your graveyard, you may return Nether Spirit to the battlefield.