Loxodon Warhammer

Equipped creature gets +3/+0 and has trample and lifelink.
Equip {3}

Auriok Champion

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

Selvala, Explorer Returned

Parley — {T}: Each player reveals the top card of their library. For each nonland card revealed this way, add {G} and you gain 1 life. Then each player draws a card.

Evolution Sage

Landfall — Whenever a land you control enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Nykthos Paragon

Whenever you gain life, you may put that many +1/+1 counters on each creature you control. Do this only once each turn.

Cradle of Vitality

Whenever you gain life, you may pay {1}{W}. If you do, put a +1/+1 counter on target creature for each 1 life you gained.

Blossoming Bogbeast

Whenever Blossoming Bogbeast attacks, you gain 2 life. Then creatures you control gain trample and get +X/+X until end of turn, where X is the amount of life you gained this turn.

Courser of Kruphix

Play with the top card of your library revealed.
You may play lands from the top of your library.
Landfall — Whenever a land you control enters, you gain 1 life.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Righteous Cause

Whenever a creature attacks, you gain 1 life.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Ezzaroot Channeler

Reach
Creature spells you cast cost {X} less to cast, where X is the amount of life you gained this turn.
{T}: You gain 2 life.

Sapseep Forest

({T}: Add {G}.)
Sapseep Forest enters tapped.
{G}, {T}: You gain 1 life. Activate only if you control two or more green permanents.

Forest

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Abiding Grace

At the beginning of your end step, choose one —
• You gain 1 life.
• Return target creature card with mana value 1 from your graveyard to the battlefield.

Fracturing Gust

Destroy all artifacts and enchantments. You gain 2 life for each permanent destroyed this way.

Lurking Predators

Whenever an opponent casts a spell, reveal the top card of your library. If it's a creature card, put it onto the battlefield. Otherwise, you may put that card on the bottom of your library.

Unflinching Courage

Enchant creature
Enchanted creature gets +2/+2 and has trample and lifelink. (Damage dealt by the creature also causes its controller to gain that much life.)

Ajani's Welcome

Whenever a creature you control enters, you gain 1 life.

Slash the Ranks

Destroy all creatures and planeswalkers except for commanders.

Serra Ascendant

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
As long as you have 30 or more life, Serra Ascendant gets +5/+5 and has flying.

Kabira Crossroads

Kabira Crossroads enters tapped.
When Kabira Crossroads enters, you gain 2 life.
{T}: Add {W}.

Infiltration Lens

Whenever equipped creature becomes blocked by a creature, you may draw two cards.
Equip {1}

Plains

Soul Warden

Whenever another creature enters, you gain 1 life.

Nature's Claim

Destroy target artifact or enchantment. Its controller gains 4 life.

Blossoming Sands

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

Hardened Scales

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

Boon Reflection

If you would gain life, you gain twice that much life instead.

Glimmerpost

When Glimmerpost enters, you gain 1 life for each Locus on the battlefield.
{T}: Add {C}.

Roots of Life

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

Sun Titan

Vigilance
Whenever Sun Titan enters or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Ajani's Mantra

At the beginning of your upkeep, you may gain 1 life.

Essence Warden

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.

Witch's Clinic

{T}: Add {C}.
{2}, {T}: Target commander gains lifelink until end of turn.

Sproutback Trudge

This spell costs {X} less to cast, where X is the amount of life you gained this turn.
Trample
At the beginning of your end step, if you gained life this turn, you may cast Sproutback Trudge from your graveyard.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Knight of Autumn

When Knight of Autumn enters, choose one —
• Put two +1/+1 counters on Knight of Autumn.
• Destroy target artifact or enchantment.
• You gain 4 life.

Ashes of the Abhorrent

Players can't cast spells from graveyards or activate abilities of cards in graveyards.
Whenever a creature dies, you gain 1 life.

Command Tower

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

Prosperous Innkeeper

When Prosperous Innkeeper enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Whenever another creature you control enters, you gain 1 life.

Terminus

Put all creatures on the bottom of their owners' libraries.
Miracle {W} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Sythis, Harvest's Hand

Whenever you cast an enchantment spell, you gain 1 life and draw a card.

Scavenging Ooze

{G}: Exile target card from a graveyard. If it was a creature card, put a +1/+1 counter on this creature and you gain 1 life.

Graypelt Refuge

Graypelt Refuge enters tapped.
When Graypelt Refuge enters, you gain 1 life.
{T}: Add {G} or {W}.

Heliod, Sun-Crowned

Indestructible
As long as your devotion to white is less than five, Heliod isn't a creature.
Whenever you gain life, put a +1/+1 counter on target creature or enchantment you control.
{1}{W}: Another target creature gains lifelink until end of turn.

Sunbond

Enchant creature
Enchanted creature has "Whenever you gain life, put that many +1/+1 counters on this creature."

Commander's Plate

Equipped creature gets +3/+3 and has protection from each color that's not in your commander's color identity.
Equip commander {3}
Equip {5}

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Angel of Destiny

Flying, double strike
Whenever a creature you control deals combat damage to a player, you and that player each gain that much life.
At the beginning of your end step, if you have at least 15 life more than your starting life total, each player Angel of Destiny attacked this turn loses the game.

Radiant Fountain

When Radiant Fountain enters, you gain 2 life.
{T}: Add {C}.

Fountain of Renewal

At the beginning of your upkeep, you gain 1 life.
{3}, Sacrifice Fountain of Renewal: Draw a card.

Felidar Sovereign

Vigilance (Attacking doesn't cause this creature to tap.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
At the beginning of your upkeep, if you have 40 or more life, you win the game.

Cosmos Elixir

At the beginning of your end step, draw a card if your life total is greater than your starting life total. Otherwise, you gain 2 life.

Basilisk Collar

Equipped creature has deathtouch and lifelink. (Any amount of damage it deals to a creature is enough to destroy it. Damage dealt by this creature also causes you to gain that much life.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Daxos, Blessed by the Sun

Daxos's toughness is equal to your devotion to white. (Each {W} in the mana costs of permanents you control counts toward your devotion to white.)
Whenever another creature you control enters or dies, you gain 1 life.

Trudge Garden

Whenever you gain life, you may pay {2}. If you do, create a 4/4 green Fungus Beast creature token with trample.

Unquestioned Authority

Enchant creature
When Unquestioned Authority enters, draw a card.
Enchanted creature has protection from creatures.

Dawn of Hope

Whenever you gain life, you may pay {2}. If you do, draw a card.
{3}{W}: Create a 1/1 white Soldier creature token with lifelink.

Leyline of Vitality

If Leyline of Vitality is in your opening hand, you may begin the game with it on the battlefield.
Creatures you control get +0/+1.
Whenever a creature you control enters, you may gain 1 life.

Seraph Sanctuary

When Seraph Sanctuary enters, you gain 1 life.
Whenever an Angel you control enters, you gain 1 life.
{T}: Add {C}.

Nyx-Fleece Ram

At the beginning of your upkeep, you gain 1 life.

Lathiel, the Bounteous Dawn

Lifelink
At the beginning of each end step, if you gained life this turn, distribute up to that many +1/+1 counters among any number of other target creatures.

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.

Authority of the Consuls

Creatures your opponents control enter tapped.
Whenever a creature an opponent controls enters, you gain 1 life.

Spike Feeder

Spike Feeder enters with two +1/+1 counters on it.
{2}, Remove a +1/+1 counter from Spike Feeder: Put a +1/+1 counter on target creature.
Remove a +1/+1 counter from Spike Feeder: You gain 2 life.

Council's Judgment

Will of the council — Starting with you, each player votes for a nonland permanent you don't control. Exile each permanent with the most votes or tied for most votes.

Cleric Class

(Gain the next level as a sorcery to add its ability.)
If you would gain life, you gain that much life plus 1 instead.
{3}{W}: Level 2
Whenever you gain life, put a +1/+1 counter on target creature you control.
{4}{W}: Level 3
When this Class becomes level 3, return target creature card from your graveyard to the battlefield. You gain life equal to that creature's toughness.

Dryad Greenseeker

{T}: Look at the top card of your library. If it's a land card, you may reveal it and put it into your hand.

Trelasarra, Moon Dancer

Whenever you gain life, put a +1/+1 counter on Trelasarra, Moon Dancer and scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Sun Droplet

Whenever you're dealt damage, put that many charge counters on Sun Droplet.
At the beginning of each upkeep, you may remove a charge counter from Sun Droplet. If you do, you gain 1 life.

Trostani, Selesnya's Voice

Whenever another creature you control enters, you gain life equal to that creature's toughness.
{1}{G}{W}, {T}: Populate. (Create a token that's a copy of a creature token you control.)

Pristine Talisman

Sunscorch Regent

Flying
Whenever an opponent casts a spell, put a +1/+1 counter on Sunscorch Regent and you gain 1 life.

Angelic Accord

At the beginning of each end step, if you gained 4 or more life this turn, create a 4/4 white Angel creature token with flying.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Soul's Attendant

Whenever another creature enters, you may gain 1 life.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Garruk's Horde

Trample
Play with the top card of your library revealed.
You may cast creature spells from the top of your library. (Do this only any time you could cast that creature spell. You still pay the spell's costs.)

Well of Lost Dreams

Whenever you gain life, you may pay {X}, where X is less than or equal to the amount of life you gained. If you do, draw X cards.