Knight of Dusk's Shadow

Menace (This creature can't be blocked except by two or more creatures.)
Your opponents can't gain life.
{1}{B}: This creature gets +1/+1 until end of turn.

Life Goes On

You gain 4 life. If a creature died this turn, you gain 8 life instead.

Kazandu Nectarpot

Landfall — Whenever a land you control enters, you gain 1 life.

Stream of Life

Dina, Soul Steeper

Whenever you gain life, each opponent loses 1 life.
{1}, Sacrifice another creature: Dina gets +X/+0 until end of turn, where X is the sacrificed creature's power.

Jungle Hollow

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

Syphon Life

Target player loses 2 life and you gain 2 life.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Kamber, the Plunderer

Partner with Laurine, the Diversion (When this creature enters, target player may put Laurine into their hand from their library, then shuffle.)
Lifelink
Whenever a creature an opponent controls dies, you gain 1 life and create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")

Roots of Life

As this enchantment enters, choose Island or Swamp.
Whenever a land of the chosen type an opponent controls becomes tapped, you gain 1 life.

Death

Return target creature card from your graveyard to the battlefield. You lose life equal to its mana value.

Life

All lands you control become 1/1 creatures until end of turn. They're still lands.