Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Rite of Consumption

As an additional cost to cast this spell, sacrifice a creature.
Rite of Consumption deals damage equal to the sacrificed creature's power to target player or planeswalker. You gain life equal to the damage dealt this way.

Death's Shadow

Death's Shadow gets -X/-X, where X is your life total.

Gather the Townsfolk

Create two 1/1 white Human creature tokens.
Fateful hour — If you have 5 or less life, create five of those tokens instead.

Angel's Grace

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
You can't lose the game this turn and your opponents can't win the game this turn. Until end of turn, damage that would reduce your life total to less than 1 reduces it to 1 instead.

Godless Shrine

({T}: Add {W} or {B}.)
As Godless Shrine enters, you may pay 2 life. If you don't, it enters tapped.

Spoils of the Vault

Choose a card name. Reveal cards from the top of your library until you reveal a card with that name, then put that card into your hand. Exile all other cards revealed this way, and you lose 1 life for each of the exiled cards.

Swamp

Isolated Chapel

Isolated Chapel enters tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

Plunge into Darkness

Choose one —
• Sacrifice any number of creatures. You gain 3 life for each creature sacrificed this way.
• Pay any amount of life, then look at that many cards from the top of your library. Put one of those cards into your hand and exile the rest.
Entwine {B} (Choose both if you pay the entwine cost.)

Plains

Near-Death Experience

At the beginning of your upkeep, if you have exactly 1 life, you win the game.

Marsh Flats

{T}, Pay 1 life, Sacrifice Marsh Flats: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Thraben Doomsayer

{T}: Create a 1/1 white Human creature token.
Fateful hour — As long as you have 5 or less life, other creatures you control get +2/+2.

Blood Celebrant

{B}, Pay 1 life: Add one mana of any color.

Faith's Shield

Target permanent you control gains protection from the color of your choice until end of turn.
Fateful hour — If you have 5 or less life, instead you and each permanent you control gain protection from the color of your choice until end of turn.