Infuse with Vitality

Until end of turn, target creature gains deathtouch and "When this creature dies, return it to the battlefield tapped under its owner's control."
You gain 2 life.

Pristine Talisman

Syphon Soul

Syphon Soul deals 2 damage to each other player. You gain life equal to the damage dealt this way.

Forest

Witherbloom Pledgemage

Magecraft — Whenever you cast or copy an instant or sorcery spell, you gain 1 life.

Vampire Neonate

{2}, {T}: Each opponent loses 1 life and you gain 1 life.

Entourage of Trest

When this creature enters, you become the monarch.
This creature can block an additional creature each combat as long as you're the monarch.

Blood Tithe

Each opponent loses 3 life. You gain life equal to the life lost this way.

Nexus Wardens

Reach
Constellation — Whenever an enchantment you control enters, you gain 2 life.

Creeping Bloodsucker

At the beginning of your upkeep, this creature deals 1 damage to each opponent. You gain life equal to the damage dealt this way.

Vegetation Abomination

Deathtouch
{T}, Sacrifice this creature: Roll a six-sided die. You gain life equal to the result.

Natural End

Destroy target artifact or enchantment. You gain 3 life.

Diregraf Scavenger

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When this creature enters, exile up to one target card from a graveyard. If a creature card was exiled this way, each opponent loses 2 life and you gain 2 life.

Vampire Envoy

Flying
Whenever this creature becomes tapped, you gain 1 life.

Gloom Sower

Whenever this creature becomes blocked by a creature, that creature's controller loses 2 life and you gain 2 life.

Vampire Spawn

When this creature enters, each opponent loses 2 life and you gain 2 life.

Kazandu Nectarpot

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

Pulse of Murasa

Return target creature or land card from a graveyard to its owner's hand. You gain 6 life.

Deathgreeter

Whenever another creature dies, you may gain 1 life.

Vicious Battlerager

When this creature enters, you take the initiative.
Spiked Retribution — Whenever this creature becomes blocked by a creature, that creature's controller loses 5 life.

Swamp

Sanguine Indulgence

This spell costs {3} less to cast if you've gained 3 or more life this turn.
Return up to two target creature cards from your graveyard to your hand.

Arcane Signet

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

Jaddi Offshoot

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

Thorn of the Black Rose

Deathtouch
When this creature enters, you become the monarch.

Epicure of Blood

Whenever you gain life, each opponent loses 1 life.

Flourishing Hunter

When this creature enters, you gain life equal to the greatest toughness among other creatures you control.

Garrulous Sycophant

At the beginning of your end step, if you're the monarch, each opponent loses 1 life and you gain 1 life.

Luxa River Shrine

{1}, {T}: You gain 1 life. Put a brick counter on this artifact.
{T}: You gain 2 life. Activate only if there are three or more brick counters on this artifact.

Grazing Gladehart

Landfall — Whenever a land you control enters, you may gain 2 life.

Essence Warden

Whenever another creature enters, you gain 1 life.

Golgari Signet

Herald of Hadar

Circle of Death — {5}{B}: Roll a d20.
1—9 | Each opponent loses 2 life.
10—19 | Each opponent loses 2 life and you gain 2 life.
20 | Each opponent loses 2 life and you gain 2 life. Create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Syphon Mind

Each other player discards a card. You draw a card for each card discarded this way.

Dawnhart Rejuvenator

When this creature enters, you gain 3 life.
{T}: Add one mana of any color.

Passageway Seer

Lifelink
When this creature enters, you take the initiative.
At the beginning of your end step, if you have the initiative, put a +1/+1 counter on this creature.

Marauding Blight-Priest

Dogged Pursuit

At the beginning of your end step, each opponent loses 1 life and you gain 1 life.

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 this creature.

Centaur Nurturer

Cruel Grimnarch

Deathtouch
When this creature enters, each opponent discards a card. For each opponent who can't, you gain 4 life.

Vampire Sovereign

Flying
When this creature enters, target opponent loses 3 life and you gain 3 life.

Gray Merchant of Asphodel

When this creature enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Filigree Familiar

When this creature enters, you gain 2 life.
When this creature dies, draw a card.

Urborg Repossession

Kicker {1}{G} (You may pay an additional {1}{G} as you cast this spell.)
Return target creature card from your graveyard to your hand. You gain 2 life. If this spell was kicked, return another target permanent card from your graveyard to your hand.

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.

Ill-Gotten Inheritance

At the beginning of your upkeep, this enchantment deals 1 damage to each opponent and you gain 1 life.
{5}{B}, Sacrifice this enchantment: It deals 4 damage to target opponent and you gain 4 life.

Social Climber

Alliance — Whenever another creature you control enters, you gain 1 life.

Orchard Elemental

Council's dilemma — When this creature enters, starting with you, each player votes for sprout or harvest. Put two +1/+1 counters on this creature for each sprout vote. You gain 3 life for each harvest vote.

Specter of the Fens

Flying
{5}{B}: Target opponent loses 2 life and you gain 2 life.

Vampire Opportunist

{6}{B}: Each opponent loses 2 life and you gain 2 life.

Tamiyo's Safekeeping

Target permanent you control gains hexproof and indestructible until end of turn. You gain 2 life. (A permanent with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)