Bishop's Soldier

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Pearl Medallion

White spells you cast cost {1} less to cast.

Elenda's Hierophant

Flying
Whenever you gain life, put a +1/+1 counter on this creature.
When this creature dies, create X 1/1 white Vampire creature tokens with lifelink, where X is its power.

Angelic Chorus

Whenever a creature you control enters, you gain life equal to its toughness.

Akroma, Vision of Ixidor

Flying, first strike, vigilance, trample
At the beginning of each combat, until end of turn, each other creature you control gets +1/+1 if it has flying, +1/+1 if it has first strike, and so on for double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, protection, reach, trample, vigilance, and partner.
Partner

Crovax, Ascendant Hero

Other white creatures get +1/+1.
Nonwhite creatures get -1/-1.
Pay 2 life: Return Crovax to its owner's hand.

Brightblade Stoat

Moonlit Wake

Whenever a creature dies, you gain 1 life.

Ajani's Sunstriker

Envoy of the Ancestors

Outlast {W} ({W}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Modified creatures you control have lifelink. (Equipment, Auras you control, and counters are modifications.)

Angelic Skirmisher

Flying
At the beginning of each combat, choose first strike, vigilance, or lifelink. Creatures you control gain that ability until end of turn.

Hunted Witness

When this creature dies, create a 1/1 white Soldier creature token with lifelink.

Charismatic Conqueror

Vigilance
Whenever an artifact or creature an opponent controls enters untapped, they may tap that permanent. If they don't, you create a 1/1 white Vampire creature token with lifelink.

The Argent Etchings

(As this Saga enters and after your draw step, add a lore counter.)
I — Incubate 2 five times, then transform all Incubator tokens you control.
II — Creatures you control get +1/+1 and gain double strike until end of turn.
III — Destroy all other permanents except for artifacts, lands, and Phyrexians. Exile this Saga, then return it to the battlefield (front face up).

Elesh Norn

Vigilance
Whenever a source an opponent controls deals damage to you or a permanent you control, that source's controller loses 2 life unless they pay {1}.
{2}{W}, Sacrifice three other creatures: Exile Elesh Norn, then return it to the battlefield transformed under its owner's control. Activate only as a sorcery.

Elesh Norn // The Argent Etchings

Voice of the Blessed

Whenever you gain life, put a +1/+1 counter on this creature.
As long as this creature has four or more +1/+1 counters on it, it has flying and vigilance.
As long as this creature has ten or more +1/+1 counters on it, it has indestructible.

Soul Warden

Whenever another creature enters, you gain 1 life.

Plains

Sol Ring

Qala, Ajani's Pridemate

Whenever Qala attacks, other attacking creatures you control get +X/+0 until end of turn, where X is the number of counters on Qala.
Whenever you gain life, put a +1/+1 counter on Qala.
{3}{W}: You gain 1 life.

Knight of Meadowgrain

First strike
Lifelink (Damage dealt by this creature also causes you to gain that much 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.

Michiko Konda, Truth Seeker

Whenever a source an opponent controls deals damage to you, that player sacrifices a permanent of their choice.

Ainok Bond-Kin

Outlast {1}{W} ({1}{W}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has first strike.

Dust Animus

Flying
If you control five or more untapped lands, this creature enters with two +1/+1 counters and a lifelink counter on it.
Plot {1}{W} (You may pay {1}{W} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Ajani's Mantra

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

Healer's Hawk

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Archangel of Thune

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Whenever you gain life, put a +1/+1 counter on each creature you control.

Gloryheath Lynx

Lifelink
Whenever this creature attacks while saddled, search your library for a basic Plains card, reveal it, put it into your hand, then shuffle.
Saddle 2 (Tap any number of other creatures you control with total power 2 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Ghostly Prison

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Aerith Gainsborough

Lifelink
Whenever you gain life, put a +1/+1 counter on Aerith Gainsborough.
When Aerith Gainsborough dies, put X +1/+1 counters on each legendary creature you control, where X is the number of +1/+1 counters on Aerith Gainsborough.

Benalish Marshal

Exemplar of Light

Flying
Whenever you gain life, put a +1/+1 counter on this creature.
Whenever you put one or more +1/+1 counters on this creature, draw a card. This ability triggers only once each turn.

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is this creature's power.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Ajani's Pridemate

Whenever you gain life, put a +1/+1 counter on this creature.

Ajani's Welcome

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

Angel of Jubilation

Flying
Other nonblack creatures you control get +1/+1.
Players can't pay life or sacrifice creatures to cast spells or activate abilities.

Gideon's Company

Whenever you gain life, put two +1/+1 counters on this creature.
{3}{W}: Put a loyalty counter on target Gideon planeswalker.

Darien, King of Kjeldor

Whenever you're dealt damage, you may create that many 1/1 white Soldier creature tokens.

Alabaster Host Sanctifier

Angel of Invention

Flying, vigilance, lifelink
Fabricate 2 (When this creature enters, put two +1/+1 counters on it or create two 1/1 colorless Servo artifact creature tokens.)
Other creatures you control get +1/+1.

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.

Celestial Unicorn

Haazda Marshal

Whenever this creature and at least two other creatures attack, create a 1/1 white Soldier creature token with lifelink.

Authority of the Consuls

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

Akroma's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Creatures you control gain flying, vigilance, and double strike until end of turn.
• Creatures you control gain lifelink, indestructible, and protection from each color until end of turn.

Beloved Princess

Lifelink
This creature can't be blocked by creatures with power 3 or greater.

Mesa Unicorn

Cosmogrand Zenith

Whenever you cast your second spell each turn, choose one —
• Create two 1/1 white Human Soldier creature tokens.
• Put a +1/+1 counter on each creature you control.

Healer's Flock

Essence Channeler

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

Arcane Signet

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

Twinblade Paladin

Whenever you gain life, put a +1/+1 counter on this creature.
As long as you have 25 or more life, this creature has double strike. (It deals both first-strike and regular combat damage.)

Anointed Chorister

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
{4}{W}: This creature gets +3/+3 until end of turn.

Daybreak Chaplain

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.

Abzan Battle Priest

Outlast {W} ({W}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has lifelink.

Abzan Falconer

Outlast {W} ({W}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has flying.

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.

Mistmeadow Skulk

Lifelink, protection from mana value 3 or greater

Celestial Crusader

Flash
Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Flying
Other white creatures get +1/+1.