Essence Warden

Whenever another creature enters, you gain 1 life.

Forest

Carnophage

At the beginning of your upkeep, tap Carnophage unless you pay 1 life.

Raving Oni-Slave

When Raving Oni-Slave enters or leaves the battlefield, you lose 3 life if you don't control a Demon.

Gurmag Angler

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Swamp

Blood Researcher

Menace (This creature can't be blocked except by two or more creatures.)
Whenever you gain life, put a +1/+1 counter on Blood Researcher.

Vault Skirge

({B/P} can be paid with either {B} or 2 life.)
Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Deglamer

Choose target artifact or enchantment. Its owner shuffles it into their library.

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Putrid Leech

Pay 2 life: Putrid Leech gets +2/+2 until end of turn. Activate only once each turn.

Faerie Macabre

Flying
Discard Faerie Macabre: Exile up to two target cards from graveyards.

Unexpected Fangs

Put a +1/+1 counter and a lifelink counter on target creature.

Chainer's Edict

Target player sacrifices a creature of their choice.
Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Mutagenic Growth

({G/P} can be paid with either {G} or 2 life.)
Target creature gets +2/+2 until end of turn.

Cast Down

Vampire Lacerator

At the beginning of your upkeep, you lose 1 life unless an opponent has 10 or less life.

Suffocating Fumes

Creatures your opponents control get -1/-1 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Wretched Anurid

Whenever another creature enters, you lose 1 life.

Jungle Hollow

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {B} or {G}.