msem-instigator

Target player discards a card and gets a poison counter.
Coalesce {4}{B}{B} (You may cast this from your graveyard for {4}{B}{B}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

As The Mistake enters, choose a card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.
Unveil {5} ({5}: Transform this. Unveil only as a sorcery.)

When The Moon Rises enters, exile all opponent's graveyards.
At the beginning of your upkeep, each opponent loses 1 life.

Codex — Out-of-Body Experience; Event Horizon; Strike from the Shadows; Second Death; Anguished Unmaking. (As this enters, conjure its contents into a shuffled face-up additional library.)
You can't draw from this codex's library.
Whenever a creature you control dies, put a card from this codex's library into your hand.

The Mythical Zhiwu enters with four +1/+1 counters on it.
{1}, Remove a +1/+1 counter from a creature you control: Target creature gets -1/-1 until end of turn. Activate only as a sorcery.
{1}, Remove a +1/+1 counter from a creature you control: Each opponent loses 1 life and you gain 1 life.

[+1]: Add {W}{U}{B}{R}{G}.
[–1]: Exile the top three cards of your library. Until end of turn, you may play cards exiled with this permanent.
[–3]: Create a 5/5 Archon creature token that's all colors and has flying and “When this creature enters, it deals 5 damage to any target.”

The Oltenen Emissary is all colors.
You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells that you cast. When you do, you may cast spells without paying their mana costs until end of turn.

{T}: Add {C}.
{2}, {T}: Choose a color, then choose one —
• Add one mana of that color for each token you control.
• Add one mana of that color for each permanent you control with one or more counters on it.

Whenever equipped creature dies, put a doom counter on The Pactbinder's Cane. Then if it has six or more doom counters on it, you may search your hand, library, and graveyard for a creature card with mana value 5 or greater, put it onto the battlefield, then shuffle. If you do, exile The Pactbinder's Cane.
Equipped creature gets +1/+0.
Equip {1}

Each player chooses a nonbasic card name, then searches each of their opponents' graveyards, hands, and libraries for any number of cards with the chosen name and exiles them. Each player shuffles, then draws a card for each card exiled from their hand this way.

Creatures you control have trample, haste, and hexproof.
{2}{G}{G}: Create a 2/2 white Cat creature token.

This spell can't be countered.
Whenever a creature you control with power 5 or greater attacks alone, it deals damage equal to its power to each opponent and to each other creature and planeswalker.

Indestructible
Spells you cast from your graveyard cost {6} less to cast.
Whenever you attack, you may cast any number of target cards from your graveyard this turn. If a spell or permanent that was cast this way would be put into a graveyard, exile it instead.

Whenever The Pyleas, Siona's Pride enters or attacks, look at the top six cards of your library. You may reveal a legendary non-Vehicle card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Crew 2

As an additional cost to cast this spell, you may tap any number of creatures you control. This spell costs {1} less to cast for each creature tapped in this way.
Create X 1/1 white Peasant creature tokens. You gain X life. Legendary creatures you control gain hexproof and indestructible until end of turn.

When The Raven Queen of Fretport enters, put a -1/-1 counter on each of any number of target creatures.
{2}{U}{B}: Proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Whenever The Resting Place deals combat damage to a player, you may return a creature card with mana value 3 or less from your graveyard to the battlefield.
Crew 2

{T}: The next time you would draw a card this turn, instead search your library for a card, put it into your hand, then shuffle. Activate only as a sorcery.

Flying
Whenever one or more other creatures die for the first time each turn, journey. (To journey, exile the top card of your library face up. Whenever a creature you control deals combat damage to an opponent, put a journeyed card you own into your hand.)

Vanguard — Whenever a creature you control attacks alone, gain control of target nonland permanent for as long as you control The Rocket Gang Strikes!.

Equipped creature gets +2/+2 and has deathtouch and lifelink.
Whenever equipped creature dies, you may exile it. If you do, return target Knight or Soldier card from your graveyard to the battlefield tapped, then attach The Roseblade to it.
Equip {2}

Equipped creature gets +2/+1. As long as it's your turn, it has deathtouch and lifelink.
{4}, Unattach The Roseblade Reforged and return it to its owner's hand: Return target Knight or Soldier creature card from your graveyard to the battlefield tapped with a finality counter on it.
Equip {3}

Siphon (Each -1/-1 counter you put on your creatures up to their remaining toughness while casting this pays for {1}.)
Draw X cards, where X is the greatest power among creatures you control. Then you may put a permanent card with mana value X or less from your hand onto the battlefield.

(Transform this if it's not attached to a creature.)
Enchant creature you control
The Scourgebone Pact's rider gets +2/+1, has flying, lifelink and deathtouch, and can't dismount. (This still transforms into a creature if its rider leaves the battlefield.)

Menace
Whenever you cast a spell from your graveyard, The Selhoff Twins deals damage equal to that spell's mana value to any target. Then copy that spell. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)