msem-instigator

Abandoned Wilderness enters the battlefield tapped if you control another nonbasic land.
{T}: Add {G} or {W}.

When Abberant Frostbringer enters the battlefield, tap up to one target creature. If you do, put two stun counters on that creature. (If a permanent with a stun counter would become untapped, remove one from it instead.)

{T}, Pay 1 life, Sacrifice Abbey of Masquerades: Create a tapped Plains token, Island token, Swamp token, Mountain token, or Forest token.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Skip your draw step.
Your maximum hand size is equal to Abhorrent Academic's power.
At the beginning of your upkeep, if you have fewer cards in your hand than your maximum hand size, draw cards equal to the difference.

At the beginning of your end step, if you're horrific, you draw a card and you lose life equal to the number of cards in your hand. (You're horrific as long as you've sacrificed a permanent or discarded a card this turn.)

Engorge (As this enters the battlefield, mill three cards, then exile a card from among the milled cards.)
When Abhorrent Exhumer enters the battlefield, if it engorged a creature card, you may return target creature card from your graveyard to your hand.

Put a +1/+1 counter on target creature. Prevent all combat damage other creatures would deal this turn.

Legendary spells you cast have nonlegendary cascade. (When you cast that spell, exile cards from the top of your library until you exile a nonlegendary nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Whenever you cast a noncreature spell, put a +1/+1 counter on Abjuration Savant. It gains flying until end of turn.
When Abjuration Savant dies, you gain life equal to its toughness.

At the beginning of your end step, you may pay {W}. If you do, exile target creature you control, then return that card to the battlefield under your control.

Counter target activated ability from a nonland source. (Mana abilities can't be targeted.)
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Haste
Whenever Abominable Auteur attacks, you may return target creature card with mana value 3 or less from your graveyard to the battlefield. If that card's mana value was 1 or less, it enters tapped and attacking.

Heretic (Whenever you cast a spell that doesn't share a color with this creature, it gets +1/+1 until end of turn.)
Discard a card: Abominable Mongrel gets +1/+1 and becomes the color of your choice until end of turn.

Trample
Whenever another Horror enters the battlefield under your control, put a +1/+1 counter on Abominable Xenoflora.

Destroy target creature with power 4 or greater. You gain 2 life.

Menace
Whenever Abomination Blackguard deals combat damage to an opponent, you may draw a card. If you do, you lose 1 life.

When Abomination Broodmother dies, create a 3/2 green Horror creature token.

When Abomination Emissary enters the battlefield, target player mills six cards.

Abomination Sculptor has deathtouch and lifelink as long as it's attacking.

Destroy target creature or planeswalker.
Crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)

Return target creature card from your graveyard to the battlefield.
Fuse (You may cast one or both halves of this card from your hand.)

Whenever you make first contact, Abrasive Citizen gets +3/+0 until end of turn. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

Abrupt Explosion deals X damage to any target.
Metamorph {X}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)

Destroy target artifact or land.

[+1]: Create a 1/1 black Faerie creature token with flying and a 2/2 white Spirit Noble creature token with lifelink.
[–X]: Target creature gets -X/-X until end of turn. Its controller loses X life.
[–7]: You get an emblem with “Whenever a permanent enters under your control, you may have it gain flying and vigilance and become a 4/4 Angel creature in addition to its other types.” (This effect lasts indefinitely.)