Case of the Uneaten Feast

Whenever a creature enters the battlefield under your control, 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.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Lay Down Arms

Exile target creature with mana value less than or equal to the number of Plains you control. Its controller gains 3 life.

Serra Ascendant

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
As long as you have 30 or more life, Serra Ascendant gets +5/+5 and has flying.

Ghostly Prison

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Surestrike Trident

Equipped creature has first strike and "{T}, Unattach Surestrike Trident: This creature deals damage equal to its power to target player or planeswalker."
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery. This card enters the battlefield unattached and stays on the battlefield if the creature leaves.)

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Vexilus Praetor

Flash
Vigilance
Aegis of the Emperor — Commanders you control have protection from everything.

Emeria, the Sky Ruin

Emeria, the Sky Ruin enters the battlefield tapped.
At the beginning of your upkeep, if you control seven or more Plains, you may return target creature card from your graveyard to the battlefield.
{T}: Add {W}.

Resplendent Angel

Flying
At the beginning of each end step, if you gained 5 or more life this turn, create a 4/4 white Angel creature token with flying and vigilance.
{3}{W}{W}{W}: Until end of turn, Resplendent Angel gets +2/+2 and gains lifelink.

Marble Diamond

Marble Diamond enters the battlefield tapped.
{T}: Add {W}.

Single Combat

Each player chooses a creature or planeswalker they control, then sacrifices the rest. Players can't cast creature or planeswalker spells until the end of your next turn.

Cleric Class

(Gain the next level as a sorcery to add its ability.)
If you would gain life, you gain that much life plus 1 instead.
{3}{W}: Level 2
Whenever you gain life, put a +1/+1 counter on target creature you control.
{4}{W}: Level 3
When this Class becomes level 3, return target creature card from your graveyard to the battlefield. You gain life equal to that creature's toughness.

Silver Shroud Costume

Flash
When Silver Shroud Costume enters the battlefield, attach it to target creature you control. That creature gains shroud until end of turn. (It can't be the target of spells or abilities.)
Equipped creature can't be blocked.
Equip {3}

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.

Throne of Eldraine

As Throne of Eldraine enters the battlefield, choose a color.
{T}: Add four mana of the chosen color. Spend this mana only to cast monocolored spells of that color.
{3}, {T}: Draw two cards. Spend only mana of the chosen color to activate this ability.

Radiant Fountain

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

Evra, Halcyon Witness

Lifelink
{4}: Exchange your life total with Evra, Halcyon Witness's power.

Beacon of Immortality

Double target player's life total. Shuffle Beacon of Immortality into its owner's library.

Deep Gnome Terramancer

Flash
Mold Earth — Whenever one or more lands enter the battlefield under an opponent's control without being played, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle. Do this only once each turn.

Ajani's Welcome

Whenever a creature enters the battlefield under your control, you gain 1 life.

Plains

Courageous Resolve

Up to one target creature you control gains protection from each of your opponents until end of turn. Draw a card. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything controlled by those players.)
Fateful hour — If you have 5 or less life, you can't lose life this turn, you can't lose the game this turn, and your opponents can't win the game this turn.

Cut a Deal

Each opponent draws a card, then you draw a card for each opponent who drew a card this way.

Suspicious Bookcase

Defender
{3}, {T}: Target creature can't be blocked this turn.

Grand Abolisher

During your turn, your opponents can't cast spells or activate abilities of artifacts, creatures, or enchantments.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Prowler's Helm

Equipped creature can't be blocked except by Walls.
Equip {2}

The One Ring

Indestructible
When The One Ring enters the battlefield, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Secret Rendezvous

You and target opponent each draw three cards.

Children of Korlis

Sacrifice Children of Korlis: You gain life equal to the life you've lost this turn. (Damage causes loss of life.)

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.

Duelist's Heritage

Whenever one or more creatures attack, you may have target attacking creature gain double strike until end of turn.

Alhammarret's Archive

If you would gain life, you gain twice that much life instead.
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Mother of Runes

{T}: Target creature you control gains protection from the color of your choice until end of turn.

Brave the Elements

Choose a color. White creatures you control gain protection from the chosen color until end of turn.

Bastion Protector

Commander creatures you control get +2/+2 and have indestructible.

Wall of Reverence

Defender, flying
At the beginning of your end step, you may gain life equal to the power of target creature you control.

Well of Lost Dreams

Whenever you gain life, you may pay {X}, where X is less than or equal to the amount of life you gained. If you do, draw X cards.

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Reprieve

Return target spell to its owner's hand.
Draw a card.

Pearl Medallion

White spells you cast cost {1} less to cast.

Manifold Key

{1}, {T}: Untap another target artifact.
{3}, {T}: Target creature can't be blocked this turn.

Test of Endurance

At the beginning of your upkeep, if you have 50 or more life, you win the game.

Giver of Runes

{T}: Another target creature you control gains protection from colorless or from the color of your choice until end of turn.

Pristine Talisman

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Rebuff the Wicked

Counter target spell that targets a permanent you control.

Akroma's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Creatures you control gain flying, vigilance, and double strike until end of turn.
• Creatures you control gain lifelink, indestructible, and protection from all colors until end of turn.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Nykthos Paragon

Whenever you gain life, you may put that many +1/+1 counters on each creature you control. Do this only once each turn.

Rhox Faithmender

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
If you would gain life, you gain twice that much life instead.

Sol Ring

Key to the City

{T}, Discard a card: Up to one target creature can't be blocked this turn.
Whenever Key to the City becomes untapped, you may pay {2}. If you do, draw a card.

Knight of the White Orchid

First strike
When Knight of the White Orchid enters the battlefield, if an opponent controls more lands than you, you may search your library for a Plains card, put it onto the battlefield, then shuffle.

Swords to Plowshares

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

Farewell

Choose one or more —
• Exile all artifacts.
• Exile all creatures.
• Exile all enchantments.
• Exile all graveyards.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

The Gaffer

At the beginning of each end step, if you gained 3 or more life this turn, draw a card.

Ranger-Captain of Eos

When Ranger-Captain of Eos enters the battlefield, you may search your library for a creature card with mana value 1 or less, reveal it, put it into your hand, then shuffle.
Sacrifice Ranger-Captain of Eos: Your opponents can't cast noncreature spells this turn.

Soul's Attendant

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

Nyx Lotus

Nyx Lotus enters the battlefield tapped.
{T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Soul Warden

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

Spirit Mantle

Enchant creature
Enchanted creature gets +1/+1 and has protection from creatures.

Chariot of Victory

Equipped creature has first strike, trample, and haste.
Equip {1}

Oketra's Monument

White creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, create a 1/1 white Warrior creature token with vigilance.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Aven Interrupter

Flash
Flying
When Aven Interrupter enters the battlefield, exile target spell. It becomes plotted. (Its owner may cast it as a sorcery on a later turn without paying its mana cost.)
Spells your opponents cast from graveyards or from exile cost {2} more to cast.

Authority of the Consuls

Creatures your opponents control enter the battlefield tapped.
Whenever a creature enters the battlefield under an opponent's control, you gain 1 life.

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Storm Herd

Create X 1/1 white Pegasus creature tokens with flying, where X is your life total.

Boon Reflection

If you would gain life, you gain twice that much life instead.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.