Plains

Aettir and Priwen

Equipped creature has base power and toughness X/X, where X is your life total.
Equip {5}

Haliya, Guided by Light

Whenever Haliya or another creature or artifact you control enters, you gain 1 life.
At the beginning of your end step, draw a card if you've gained 3 or more life this turn.
Warp {W} (You may cast this card from your hand for its warp cost. Exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)

Krovod Haunch

Equipped creature gets +2/+0.
{2}, {T}, Sacrifice this Equipment: You gain 3 life.
When this Equipment is put into a graveyard from the battlefield, you may pay {1}{W}. If you do, create two 1/1 white Dog creature tokens.
Equip {2}

Angel of Vitality

Flying
If you would gain life, you gain that much life plus 1 instead.
This creature gets +2/+2 as long as you have 25 or more life.

Ajani's Pridemate

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

Ancestor Dragon

Flying
Whenever one or more creatures you control attack, you gain 1 life for each attacking creature.

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.

Restoration Magic

Tiered (Choose one additional cost.)
• Cure — {0} — Target permanent gains hexproof and indestructible until end of turn.
• Cura — {1} — Target permanent gains hexproof and indestructible until end of turn. You gain 3 life.
• Curaga — {3}{W} — Permanents you control gain hexproof and indestructible until end of turn. You gain 6 life.

Eriette's Lullaby

Destroy target tapped creature. You gain 2 life.

Holy Cow

Flash
Flying
When this creature enters, you gain 2 life and scry 1. (Look at the top card of your library. You may put that card on the bottom.)

The Wind Crystal

White spells you cast cost {1} less to cast.
If you would gain life, you gain twice that much life instead.
{4}{W}{W}, {T}: Creatures you control gain flying and lifelink until end of turn.

Aunt May

Whenever another creature you control enters, you gain 1 life. If it's a Spider, put a +1/+1 counter on it.

Battle Menu

Choose one —
• Attack — Create a 2/2 white Knight creature token.
• Ability — Target creature gets +0/+4 until end of turn.
• Magic — Destroy target creature with power 4 or greater.
• Item — You gain 4 life.

Prayer of Binding

Flash
When this enchantment enters, exile up to one target nonland permanent an opponent controls until this enchantment leaves the battlefield. You gain 2 life.

Charming Prince

When this creature enters, choose one —
• Scry 2.
• You gain 3 life.
• Exile another target creature you own. Return it to the battlefield under your control at the beginning of the next end step.

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.)

Authority of the Consuls

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