Auriok Champion

Protection from black and from red
Whenever another creature enters, you may gain 1 life.

Soul Warden

Whenever another creature enters, you gain 1 life.

Ashnod's Altar

Sheoldred, the Apocalypse

Deathtouch
Whenever you draw a card, you gain 2 life.
Whenever an opponent draws a card, they lose 2 life.

Animation Module

Whenever one or more +1/+1 counters are put on a permanent you control, you may pay {1}. If you do, create a 1/1 colorless Servo artifact creature token.
{3}, {T}: Choose a counter on target permanent or player. Give that permanent or player another counter of that kind.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Karlov of the Ghost Council

Whenever you gain life, put two +1/+1 counters on Karlov of the Ghost Council.
{W}{B}, Remove six +1/+1 counters from Karlov of the Ghost Council: Exile target creature.