Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Elvish Mystic

Healer's Hawk

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

Essence Warden

Whenever another creature enters, you gain 1 life.

Blossoming Sands

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

Kor Celebrant

Whenever Kor Celebrant or another creature you control enters, you gain 1 life.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Radiant Fountain

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

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.)

Priest of Ancient Lore

When Priest of Ancient Lore enters, you gain 1 life and draw a card.

Ajani's Mantra

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

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.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Kazandu Nectarpot

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

Soul's Attendant

Whenever another creature enters, you may gain 1 life.

Avacyn's Pilgrim

Jaddi Offshoot

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

Kodama's Reach

Celestial Unicorn

Whenever you gain life, put a +1/+1 counter on Celestial Unicorn.

Kabira Crossroads

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

Impassioned Orator

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

Pristine Talisman

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.)

Soul Warden

Answered Prayers

Whenever a creature you control enters, you gain 1 life. If Answered Prayers isn't a creature, it becomes a 3/3 Angel creature with flying in addition to its other types until end of turn.

Llanowar Elves

Luminous Phantom

Flying
Whenever another creature you control leaves the battlefield, you gain 1 life.
If Luminous Phantom would be put into a graveyard from anywhere, exile it instead.

Lunarch Veteran

Whenever another creature you control enters, you gain 1 life.
Disturb {1}{W} (You may cast this card from your graveyard transformed for its disturb cost.)

Lunarch Veteran // Luminous Phantom

Fyndhorn Elves

Revitalize

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.