Will, Scion of Peace

Vigilance
{T}: Spells you cast this turn that are white and/or blue cost {X} less to cast, where X is the amount of life you gained this turn. Activate only as a sorcery.

Metropolis Reformer

Flying, vigilance
You have hexproof.
Whenever this creature is dealt damage, you gain that much life.

Hope Estheim

Lifelink
At the beginning of your end step, each opponent mills X cards, where X is the amount of life you gained this turn.

Case of the Uneaten Feast

Whenever a creature you control enters, you gain 1 life.
To solve — You've gained 5 or more life this turn. (If unsolved, solve at the beginning of your end step.)
Solved — Sacrifice this Case: Creature cards in your graveyard gain "You may cast this card from your graveyard" until end of turn.

Absorb

Blossoming Calm

You gain hexproof until your next turn. You gain 2 life.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Cathedral Sanctifier

When this creature enters, you gain 3 life.

Relic of Progenitus

{T}: Target player exiles a card from their graveyard.
{1}, Exile this artifact: Exile all graveyards. Draw a card.

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.

Martyr of Sands

{1}, Reveal X white cards from your hand, Sacrifice this creature: You gain three times X life.

Space-Time Anomaly

Target player mills cards equal to your life total.

Sphinx's Revelation

Auriok Champion

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

Dovin Baan

+1: Until your next turn, up to one target creature gets -3/-0 and its activated abilities can't be activated.
−1: You gain 2 life and draw a card.
−7: You get an emblem with "Your opponents can't untap more than two permanents during their untap steps."

Teferi, Who Slows the Sunset

+1: Choose up to one target artifact, up to one target creature, and up to one target land. Untap the chosen permanents you control. Tap the chosen permanents you don't control. You gain 2 life.
−2: Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.
−7: You get an emblem with "Untap all permanents you control during each opponent's untap step" and "You draw a card during each opponent's draw step."