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 of your library.)

Plains

Soul Warden

Whenever another creature enters the battlefield, you gain 1 life.

Swords to Plowshares

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

Prey Upon

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Ajani's Pridemate

Whenever you gain life, put a +1/+1 counter on Ajani's Pridemate.

Voice of the Blessed

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

Sunstrike Legionnaire

Sunstrike Legionnaire doesn't untap during your untap step.
Whenever another creature enters the battlefield, untap Sunstrike Legionnaire.
{T}: Tap target creature with mana value 3 or less.

Angel of Vitality

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

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 enters the battlefield under your control, you may gain 1 life.

Gods Willing

Target creature you control gains protection from the color of your choice until end of turn. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything of that color.)
Scry 1.

Forest

Shelter

Target creature you control gains protection from the color of your choice until end of turn.
Draw a card.

Blossoming Sands

Blossoming Sands enters the battlefield tapped.
When Blossoming Sands enters the battlefield, you gain 1 life.
{T}: Add {G} or {W}.

Presence of Gond

Enchant creature
Enchanted creature has "{T}: Create a 1/1 green Elf Warrior creature token."

Aura Mutation

Destroy target enchantment. Create X 1/1 green Saproling creature tokens, where X is that enchantment's mana value.

Prosperous Innkeeper

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