The Lost Caverns of Ixalan

Malicious Eclipse | Sorcery | | All creatures get -2/-2 until end of turn. If a creature an opponent controls would die this turn, exile it instead. | Campbell White

Soulcoil Viper | Creature | Snake | {B}, {T}, Sacrifice Soulcoil Viper: Return target creature card from your graveyard to the battlefield with a finality counter on it. Activate only as a sorcery. (If a creature with a finality counter on it would die, exile it instead.) | Allen Douglas

Stinging Cave Crawler | Creature | Insect Horror | Deathtouch Descend 4 — Whenever Stinging Cave Crawler attacks, if there are four or more permanent cards in your graveyard, you draw a card and you lose 1 life. | Dan Scott

Synapse Necromage | Creature | Fungus Wizard | When Synapse Necromage dies, create two 1/1 black Fungus creature tokens with "This creature can't block." | Piotr Foksowicz

Akawalli, the Seething Tower | Legendary Creature | Fungus | Descend 4 — As long as there are four or more permanent cards in your graveyard, Akawalli, the Seething Tower gets +2/+2 and has trample. Descend 8 — As long as there are eight or more permanent cards in your graveyard, Akawalli gets an additional +2/+2 and can't be blocked by more than one creature. | Simon Dominic