My Forces Are Innumerable

(An ongoing scheme remains face up until it's abandoned.)
At the beginning of your end step, create a 3/3 black Horror creature token.
At the beginning of your opponents' end step, they may sacrifice two creatures of their choice. If they do, abandon this scheme.

Swamp

Nihil Spellbomb

{T}, Sacrifice Nihil Spellbomb: Exile target player's graveyard.
When Nihil Spellbomb is put into a graveyard from the battlefield, you may pay {B}. If you do, draw a card.

Mnemonic Betrayal

Exile all opponents' graveyards. You may cast spells from among those cards this turn, and mana of any type can be spent to cast them. At the beginning of the next end step, if any of those cards remain exiled, return them to their owners' graveyards.
Exile Mnemonic Betrayal.

Tooth, Claw, and Tail

When you set this scheme in motion, destroy up to three target nonland permanents.

Dance, Pathetic Marionette

When you set this scheme in motion, each opponent reveals cards from the top of their library until they reveal a creature card. Choose one of the revealed creature cards and put it onto the battlefield under your control. Put all other cards revealed this way into their owners' graveyards.

Consuming Aberration

Consuming Aberration's power and toughness are each equal to the number of cards in your opponents' graveyards.
Whenever you cast a spell, each opponent reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard.

Ashiok, Dream Render

Spells and abilities your opponents control can't cause their controller to search their library.
−1: Target player mills four cards. Then exile each opponent's graveyard.

Psychic Corrosion

Whenever you draw a card, each opponent mills two cards.

Vicious Rumors

Vicious Rumors deals 1 damage to each opponent. Each opponent discards a card, then mills a card. You gain 1 life.

Death's Approach

Enchant creature
Enchanted creature gets -X/-X, where X is the number of creature cards in its controller's graveyard.

Your Fate Is Thrice Sealed

When you set this scheme in motion, reveal the top three cards of your library. Put all land cards revealed this way onto the battlefield and the rest into your hand.

I Bask in Your Silent Awe

(An ongoing scheme remains face up until it's abandoned.)
Each opponent can't cast more than one spell each turn.
At the beginning of your upkeep, if no opponent cast a spell since your last turn ended, abandon this scheme.

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Choose Your Champion

When you set this scheme in motion, target opponent chooses a player. Until your next turn, only you and the chosen player can cast spells and attack with creatures.

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.

Siren of the Silent Song

Flying
Inspired — Whenever Siren of the Silent Song becomes untapped, each opponent discards a card, then each opponent mills a card.

Manic Scribe

When Manic Scribe enters, each opponent mills three cards.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, that player mills three cards.

All in Good Time

When you set this scheme in motion, take an extra turn after this one. Schemes can't be set in motion that turn.

Imprison This Insolent Wretch

(An ongoing scheme remains face up until it's abandoned.)
When you set this scheme in motion, choose an opponent.
Permanents the chosen player controls don't untap during their untap step.
When the chosen player is attacked or becomes the target of a spell or ability, abandon this scheme.

Fetid Pools

({T}: Add {U} or {B}.)
Fetid Pools enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Mind Grind

Each opponent reveals cards from the top of their library until they reveal X land cards, then puts all cards revealed this way into their graveyard. X can't be 0.

Bow to My Command

(An ongoing scheme remains face up until it's abandoned.)
As you set this scheme in motion, choose an opponent.
Creatures the chosen player controls can't attack you or planeswalkers you control.
At the beginning of your opponents' end step, they may tap any number of untapped creatures they control with total power 8 or greater. If they do, abandon this scheme.

Behold the Power of Destruction

When you set this scheme in motion, destroy all nonland permanents target opponent controls.

Island

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Plots That Span Centuries

When you set this scheme in motion, the next time you would set a scheme in motion, set three schemes in motion instead.

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.