msem-instigator

Enchant opponent
Creatures enchanted player controls get -2/-2.
Whenever enchanted player casts a noncreature spell, they lose 2 life and you gain 2 life.

This spell costs {X} less to cast, where X is the power of the creature it targets.
Tyrant's Reckoning deals 4 damage to target creature.

Menace
Whenever Diregraf Skulleater deals combat damage to a player, that player discards a card.
Whenever one or more cards leave your graveyard, put a +1/+1 counter on Diregraf Skulleater.

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature can't attack or block.
At the beginning of your upkeep, you gain 1 life.

Flying
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Whenever Outrider Captain attacks, search your library for a creature card with mana value 1 or less, put it onto the battlefield tapped and attacking, then shuffle.

When you unveil Shining Elementalist, creatures can't block this turn.

Flash
Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
When Grim enters, if you sacrificed a permanent this turn, exile target tapped creature.

Double the number of each kind of counter on target creature you control.

{T}: Add {C}.
{2}, {T}, Sacrifice Rugged Expanse: Put a +1/+1 counter on target creature. It gains vigilance until end of turn. Activate only as a sorcery.

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

Destroy target creature with mana value X or less.

{G}, {T}: Add {C}{C}.

{1}: Draw a card, then put a card from your hand on top of your library.

Equipped creature gets +1/+1 and has double strike.
Equip {2}{R}
Madness {2}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)
When Dwarven War Hatchet enters, if you cast it for its madness cost, attach it to target creature you control.

At the beginning of each combat, harmonize twice. (To harmonize, trigger up to one harmony of a permanent you control.)
Harmony — Target creature gets +1/+1 and your choice of flying, haste, or vigilance until end of turn.

Draw three cards, then reveal your hand.

When Ragantiar enters, mill five cards.
{3}{B}, Sacrifice a creature: Return target creature card with power X or less from your graveyard to the battlefield, where X is 1 plus the sacrificed creature's power.

{G}, {T}, Remove a +1/+1 counter from a creature you control: Create a 2/2 green Ox creature token.

Flying
Mind's Contagion has haste as long as there are two or more creature cards in your graveyard.
Whenever Mind's Contagion deals combat damage to a player, until your next turn, it gains “Noncreature spells opponents cast cost an additional 2 life to cast.”

When The Third Breach enters, discard your hand, then draw seven cards.
Creatures you control get +3/+3, have haste, and are Horrors in addition to their other types.
At the beginning of each end step, sacrifice each creature you control.

Whenever a nontoken creature dies, you may exile that card from its owner's graveyard. If you do, return each other card exiled with Prop Recycling to its owner's graveyard.
At the beginning of combat on your turn, create a token that's a copy of a card exiled with Prop Recycling.

Converge — Destroy up to X target artifacts or enchantments, where X is the number of colors of mana spent to cast Bury the Past.

As an additional cost to cast this spell, discard a card.
Draw two cards and create a Treasure token.

Whenever Zealous Scaleblight becomes tapped, it deals 1 damage to any target.

Solar Hatching deals 4 damage to each creature.
Coalesce {6}{R}{R} (You may cast this from your graveyard for {6}{R}{R}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
When Solar Hatching enters, each player chooses up to two lands they control and sacrifices the rest.