Seal of Cleansing

Sacrifice Seal of Cleansing: Destroy target artifact or enchantment.

Selfless Spirit

Flying
Sacrifice Selfless Spirit: Creatures you control gain indestructible until end of turn.

Augur il-Vec

Shadow (This creature can block or be blocked by only creatures with shadow.)
Sacrifice Augur il-Vec: You gain 4 life. Activate only during your upkeep.

Benevolent Bodyguard

Sacrifice Benevolent Bodyguard: Target creature you control gains protection from the color of your choice until end of turn.

Bubbling Cauldron

{1}, {T}, Sacrifice a creature: You gain 4 life.
{1}, {T}, Sacrifice a creature named Festering Newt: Each opponent loses 4 life. You gain life equal to the life lost this way.

Keening Apparition

Sacrifice Keening Apparition: Destroy target enchantment.

Ashnod's Altar

Astrid Peth

Whenever Astrid Peth enters or attacks, create a Food token.
Brand-new Sky — Whenever you sacrifice a Clue or Food, Astrid Peth explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Martyr of Sands

{1}, Reveal X white cards from your hand, Sacrifice Martyr of Sands: You gain three times X life.

Caregiver

{W}, Sacrifice a creature: Prevent the next 1 damage that would be dealt to any target this turn.

Blasting Station

{T}, Sacrifice a creature: Blasting Station deals 1 damage to any target.
Whenever a creature enters, you may untap Blasting Station.

Claws of Gix

{1}, Sacrifice a permanent: You gain 1 life.

Alseid of Life's Bounty

Lifelink
{1}, Sacrifice Alseid of Life's Bounty: Target creature or enchantment you control gains protection from the color of your choice until end of turn.

Auriok Replica

{W}, Sacrifice Auriok Replica: Prevent all damage a source of your choice would deal to you this turn.

Bottle Gnomes

Sacrifice Bottle Gnomes: You gain 3 life.

Selfless Savior

Sacrifice Selfless Savior: Another target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Dedicated Martyr

{W}, Sacrifice Dedicated Martyr: You gain 3 life.

Life Chisel

Sacrifice a creature: You gain life equal to the sacrificed creature's toughness. Activate only during your upkeep.

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

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.

Celestine, the Living Saint

Flying, lifelink
Healing Tears — At the beginning of your end step, return target creature card with mana value X or less from your graveyard to the battlefield, where X is the amount of life you gained this turn.

Angelic Renewal

Whenever a creature is put into your graveyard from the battlefield, you may sacrifice Angelic Renewal. If you do, return that card to the battlefield.

Ravenous Amulet

{1}, {T}, Sacrifice a creature: Draw a card and put a soul counter on this artifact. Activate only as a sorcery.
{4}, {T}, Sacrifice this artifact: Each opponent loses life equal to the number of soul counters on this artifact.

By Invitation Only

Choose a number between 0 and 13. Each player sacrifices that many creatures of their choice.