Fraying Sanity

Enchant player
At the beginning of each end step, enchanted player mills X cards, where X is the number of cards put into their graveyard from anywhere this turn.

Cut Your Losses

Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Target player mills half their library, rounded down.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Jeweled Lotus

{T}, Sacrifice this artifact: Add three mana of any one color. Spend this mana only to cast your commander.

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Gravecrawler

This creature can't block.
You may cast this card from your graveyard as long as you control a Zombie.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Mycosynth Lattice

All permanents are artifacts in addition to their other types.
All cards that aren't on the battlefield, spells, and permanents are colorless.
Players may spend mana as though it were mana of any color.

Possibility Storm

Whenever a player casts a spell from their hand, that player exiles it, then exiles cards from the top of their library until they exile a card that shares a card type with it. That player may cast that card without paying its mana cost. Then they put all cards exiled with this enchantment on the bottom of their library in a random order.

Obliterate

This spell can't be countered.
Destroy all artifacts, creatures, and lands. They can't be regenerated.

Mishra, Eminent One

At the beginning of combat on your turn, create a token that's a copy of target noncreature artifact you control, except its name is Mishra's Warform and it's a 4/4 Construct artifact creature in addition to its other types. It gains haste until end of turn. Sacrifice it at the beginning of the next end step.

Stranglehold

Your opponents can't search libraries.
If an opponent would begin an extra turn, that player skips that turn instead.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Mountain

Swamp

Sol Ring

Forest

Omniscience

You may cast spells from your hand without paying their mana costs.

Spy Kit

Equipped creature gets +1/+1 and has all names of nonlegendary creature cards in addition to its name.
Equip {2}

Static Orb

As long as this artifact is untapped, players can't untap more than two permanents during their untap steps.

Commander's Sphere

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

Liquimetal Coating

{T}: Target permanent becomes an artifact in addition to its other types until end of turn.

Hellkite Tyrant

Flying, trample
Whenever Hellkite Tyrant deals combat damage to a player, gain control of all artifacts that player controls.
At the beginning of your upkeep, if you control twenty or more artifacts, you win the game.

Island

Niv-Mizzet, Parun

This spell can't be countered.
Flying
Whenever you draw a card, Niv-Mizzet deals 1 damage to any target.
Whenever a player casts an instant or sorcery spell, you draw a card.

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is this creature's power.

Mana Crypt

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

Natural Affinity

All lands become 2/2 creatures until end of turn. They're still lands.

Guardian Zendikon

Enchant land
Enchanted land is a 2/6 white Wall creature with defender. It's still a land.
When enchanted land dies, return that card to its owner's hand.

Splinter

Exile target artifact. Search its controller's graveyard, hand, and library for all cards with the same name as that artifact and exile them. Then that player shuffles.

Arcane Laboratory

Each player can't cast more than one spell each turn.

Bazaar Trader

{T}: Target player gains control of target artifact, creature, or land you control.

Wind Zendikon

Enchant land
Enchanted land is a 2/2 blue Elemental creature with flying. It's still a land.
When enchanted land dies, return that card to its owner's hand.

Animate Land

Until end of turn, target land becomes a 3/3 creature that's still a land.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Jodah, Archmage Eternal

Flying
You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.

Collector Ouphe

Activated abilities of artifacts can't be activated.

Humility

All creatures lose all abilities and have base power and toughness 1/1.

Crusher Zendikon

Enchant land
Enchanted land is a 4/2 red Beast creature with trample. It's still a land.
When enchanted land dies, return that card to its owner's hand.

Maddening Cacophony

Kicker {3}{U}
Each opponent mills eight cards. If this spell was kicked, instead each opponent mills half their library, rounded up.

Decree of Annihilation

Exile all artifacts, creatures, and lands from the battlefield, all cards from all graveyards, and all cards from all hands.
Cycling {5}{R}{R} ({5}{R}{R}, Discard this card: Draw a card.)
When you cycle this card, destroy all lands.

Bruvac the Grandiloquent

If an opponent would mill one or more cards, they mill twice that many cards instead. (To mill a card, a player puts the top card of their library into their graveyard.)

Mindslaver

{4}, {T}, Sacrifice Mindslaver: You control target player during that player's next turn. (You see all cards that player could see and make all decisions for the player.)

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Winter Orb

As long as this artifact is untapped, players can't untap more than one land during their untap steps.

Bitter Ordeal

Search target player's library for a card and exile it. Then that player shuffles.
Gravestorm (When you cast this spell, copy it for each permanent put into a graveyard this turn. You may choose new targets for the copies.)

Myr Landshaper

{T}: Target land becomes an artifact in addition to its other types until end of turn.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Timeless Lotus

Timeless Lotus enters tapped.
{T}: Add {W}{U}{B}{R}{G}.

Maralen of the Mornsong

Players can't draw cards.
At the beginning of each player's draw step, that player loses 3 life, searches their library for a card, puts it into their hand, then shuffles.

Eradicate

Exile target nonblack creature. Search its controller's graveyard, hand, and library for all cards with the same name as that creature and exile them. Then that player shuffles.

Phyresis

Enchant creature
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)