msem-instigator

Flying
Creatures your opponents control get -1/-0.

Reach, trample
Deploy 6 (As this enters, you may tap any number of other creatures you control with total power 6 or more.)
When Glaistig of Wild Hunts enters, if it was cast and deployed, untap all lands you control.

Flash
As an additional cost to cast this spell, sacrifice a creature or pay {2}.
Defender

Flying
Deploy 3 (As this enters, you may tap any number of other creatures you control with total power 3 or more.)
When Grasping Choir enters, you may exile target creature if it's tapped or if Grasping Choir was deployed.

Menace
Disgraced 1 (This enters with a -1/-1 counter. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)

Whenever another nonland creature you control dies, return it to the battlefield tapped with a sapling counter on it. It becomes an Animus land named Bitter Hazel, loses all other card types, and gains “{T}: Add {G}” and “Pay this card's mana cost: This land becomes a creature until end of turn. It's still a land.”

When Growth Paradigm enters the battlefield, conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)
Once each turn, when you cast a sorcery spell, you may create an X/X green Mutant creature token, where X is that spell's mana value.

Untap target artifact or creature. It gains hexproof and indestructible until end of turn.

Destroy target nonland permanent.
If you've sacrificed a permanent this turn, draw a card.

Flash
Flying
Whenever H13 Wasp enters or you cast an another spell with flash or an instant, exile up to one target nonland permanent. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Hexproof
Deploy 4 (As this enters, you may tap any number of other creatures you control with total power 4 or more.)
When Hamlet Witch enters deployed, return target card from your graveyard to your hand.

When Hardlight Visionary enters the battlefield, create a Function token with “Until end of turn, target creature becomes a 5/5 Dragon and gains flying.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

{T}, Pay 1 life: Add {W} or {U}.
{2}, {T}, Sacrifice Haunted Manor and another permanent: Draw a card. Activate only during your turn.

Disgraced 5 (This enters with five -1/-1 counters. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
Prevent all combat damage that would be dealt to Heir Unapparent.

Destroy target artifact or land. If a land was destroyed this way, its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

{T}: Add one mana of any color. When you spend this mana to cast a spell with mana value 5 or greater, put two +1/+1 counters on Herald of the New Divinity.

When Hermetic Fisher dies, you may return target creature to its owner's hand.

Flash
Whenever you cast another spell with flash or an instant, put a +1/+1 counter on High Street Shadow.

When Honey Pot enters the battlefield, create two 1/1 black Demon enchantment creature tokens with breach and “This creature can't block.” (Whenever it deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
Whenever a Curse you control becomes attached to an opponent, that player loses 1 life and you gain 1 life.

When you attain Hopeless Lanonshee, create two 1/1 black Construct artifact creature tokens.
Whenever a creature dies, each opponent loses 1 life and you gain 1 life.

Whenever Hopeless Romantic or another creature you control dies, each opponent loses 1 life.
Attain {3}{B} ({3}{B}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

{T}: Hotblooded Sorcerer deals 1 damage to target player or planeswalker.
Attain {3}{R} ({3}{R}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Enchant creature
As Hunter's Distinction enters, you may tap enchanted creature if it's untapped. When you do, put three -1/-1 counters on target creature with flying.
Enchanted creature gets +3/+2 and has reach.

Reach
Deploy 3 (As this enters, you may tap any number of other creatures you control with total power 3 or more.)
When Hunting Company enters deployed, destroy target creature with flying.

Creatures you control have “{T}: Add {C} or one mana of any of this creature's colors.”
Attain {5}{G} ({5}{G}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)