Circular Logic

Counter target spell unless its controller pays {1} for each card in your graveyard.
Madness {U} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Daring Demolition

Thalia's Lancers

First strike
When Thalia's Lancers enters, you may search your library for a legendary card, reveal it, put it into your hand, then shuffle.

Island

Boompile

{T}: Flip a coin. If you win the flip, destroy all nonland permanents.

Bulwark Giant

When Bulwark Giant enters, you gain 5 life.

Blossoming Sands

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {G} or {W}.

Swamp

Thought Collapse

Counter target spell. Its controller mills three cards.

Drag Under

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

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
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.)

Lich's Mirror

If you would lose the game, instead shuffle your hand, your graveyard, and all permanents you own into your library, then draw seven cards and your life total becomes 20.

Celestial Kirin

Flying
Whenever you cast a Spirit or Arcane spell, destroy all permanents with that spell's mana value.

Deadbridge Shaman

When Deadbridge Shaman dies, target opponent discards a card.

Cathar's Companion

Whenever you cast a noncreature spell, Cathar's Companion gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Sunrise Seeker

Vigilance
When Sunrise Seeker enters, it 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.)

Storm Sculptor

Storm Sculptor can't be blocked.
When Storm Sculptor enters, return a creature you control to its owner's hand.

Plains

Solemn Simulacrum

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

Dark Withering

Destroy target nonblack creature.
Madness {B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

The Eldest Reborn

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Each opponent sacrifices a creature or planeswalker of their choice.
II — Each opponent discards a card.
III — Put target creature or planeswalker card from a graveyard onto the battlefield under your control.

Catalog

Shriekmaw

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When Shriekmaw enters, destroy target nonartifact, nonblack creature.
Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Spectral Gateguards

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Spectral Gateguards is paired with another creature, both creatures have vigilance.

Norn's Annex

({W/P} can be paid with either {W} or 2 life.)
Creatures can't attack you or planeswalkers you control unless their controller pays {W/P} for each of those creatures.

Dismantling Blow

Kicker {2}{U} (You may pay an additional {2}{U} as you cast this spell.)
Destroy target artifact or enchantment. If this spell was kicked, draw two cards.

Moonlit Strider

Sacrifice Moonlit Strider: Target creature you control gains protection from the color of your choice until end of turn.
Soulshift 3 (When this creature dies, you may return target Spirit card with mana value 3 or less from your graveyard to your hand.)

Whiplash Trap

If an opponent had two or more creatures enter the battlefield under their control this turn, you may pay {U} rather than pay this spell's mana cost.
Return two target creatures to their owners' hands.

Suspicious Bookcase

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

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

Martyr's Cause

Sacrifice a creature: The next time a source of your choice would deal damage to any target this turn, prevent that damage.

Lay Claim

Enchant permanent
You control enchanted permanent.
Cycling {2} ({2}, Discard this card: Draw a card.)

Will-o'-the-Wisp

Flying (This creature can't be blocked except by creatures with flying or reach.)
{B}: Regenerate Will-o'-the-Wisp. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Darksteel Mutation

Enchant creature
Enchanted creature is an Insect artifact creature with base power and toughness 0/1 and has indestructible, and it loses all other abilities, card types, and creature types.

Shipwreck Singer

Flying
{1}{U}: Target creature an opponent controls attacks this turn if able.
{1}{B}, {T}: Attacking creatures get -1/-1 until end of turn.

Street Wraith

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Cycling—Pay 2 life. (Pay 2 life, Discard this card: Draw a card.)

Contraband Kingpin

Lifelink
Whenever an artifact you control enters, scry 1.

Alchemist's Vial

When Alchemist's Vial enters, draw a card.
{1}, {T}, Sacrifice Alchemist's Vial: Target creature can't attack or block this turn.

Mishra's Factory

{T}: Add {C}.
{1}: Mishra's Factory becomes a 2/2 Assembly-Worker artifact creature until end of turn. It's still a land.
{T}: Target Assembly-Worker creature gets +1/+1 until end of turn.

Beacon of Immortality

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

Thraben Foulbloods

Delirium — Thraben Foulbloods gets +1/+1 and has menace as long as there are four or more card types among cards in your graveyard. (A creature with menace can't be blocked except by two or more creatures.)

Extract from Darkness

Each player mills two cards. Then you put a creature card from a graveyard onto the battlefield under your control.

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}