Amalia Benavides Aguirre

Ward—Pay 3 life.
Whenever you gain life, Amalia Benavides Aguirre explores. Then destroy all other creatures if its power is exactly 20. (To have this creature explore, reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Elenda, Saint of Dusk

Lifelink, hexproof from instants
As long as your life total is greater than your starting life total, Elenda gets +1/+1 and has menace. Elenda gets an additional +5/+5 as long as your life total is at least 10 greater than your starting life total.

Essence Channeler

As long as you've lost life this turn, Essence Channeler has flying and vigilance.
Whenever you gain life, put a +1/+1 counter on Essence Channeler.
When Essence Channeler dies, put its counters on target creature you control.

Guide of Souls

Whenever another creature you control enters, you gain 1 life and get {E} (an energy counter).
Whenever you attack, you may pay {E}{E}{E}. When you do, put two +1/+1 counters and a flying counter on target attacking creature. It becomes an Angel in addition to its other types.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Vito, Thorn of the Dusk Rose

Whenever you gain life, target opponent loses that much life.
{3}{B}{B}: Creatures you control gain lifelink until end of turn.

Blind Obedience

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Artifacts and creatures your opponents control enter tapped.

Soul's Attendant

Whenever another creature enters, you may gain 1 life.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Arcane Signet

Soul Warden

Whenever another creature enters, you gain 1 life.

Lunar Convocation

At the beginning of your end step, if you gained life this turn, each opponent loses 1 life.
At the beginning of your end step, if you gained and lost life this turn, create a 1/1 black Bat creature token with flying.
{1}{B}, Pay 2 life: Draw a card.

Bloodthirsty Conqueror

Flying, deathtouch
Whenever an opponent loses life, you gain that much life. (Damage causes loss of life.)

Isolated Chapel

Isolated Chapel enters tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

Suture Priest

Whenever another creature you control enters, you may gain 1 life.
Whenever a creature an opponent controls enters, you may have that player lose 1 life.

Kambal, Consul of Allocation

Whenever an opponent casts a noncreature spell, that player loses 2 life and you gain 2 life.

Bartolomé del Presidio

Sacrifice another creature or artifact: Put a +1/+1 counter on Bartolomé del Presidio.