msem-instigator

When Hold Captive enters, exile another target nonland permanent until Hold Captive leaves the battlefield.
When Hold Captive enters, recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)

Creatures you control get +1/+4 until end of turn.

Hollow Queen can't be blocked by tokens.
Whenever Hollow Queen deals combat damage to a player or planeswalker, you may remove a counter from a permanent you control. If you do, put a +1/+1 counter on target creature you control.

When Hollowflesh Ghoul dies, create a 1/1 black Skeleton creature token.

Hollowghast, the Iron Phantom enters with three +1/+1 counters on it.
If damage would be dealt to Hollowghast, prevent that damage. Remove a +1/+1 counter from Hollowghast.

At the beginning of your upkeep, put a crop counter on Homestead.
{G/W}, Remove a crop counter from Homestead: Put a +1/+1 counter on target creature.
{G/W}, Remove three crop counters from Homestead: Put a +1/+1 counter on each creature you control.

When Honey Pot enters, 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 Honored Retinue enters, choose a creature you control. You may search your library for a creature card with the same name as that creature, reveal it, put it into your hand, then shuffle.

Flying
Whenever a Harpy you control becomes the target of a spell, scry 1.

Create a token that's a copy of target creature you control, except it has base power and toughness 2/2.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Pressure {U} (You may cast this spell for its pressure cost if there are seven or more cards in your graveyard.)

When Horizon Gazer enters, reveal the top two cards of your library. Put a noncreature card revealed this way into your hand and the rest into your graveyard.
Ascend {3}{G} ({3}{G}: Exile this creature, then return it to the battlefield transformed. Ascend only as a sorcery.)

Flying
Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
At the beginning of combat on your turn, if you're in a renaissance, target creature gains flying until end of turn.

When Horizon Treader enters, you may exile target enchantment you control. Return that card to the battlefield under your control at the beginning of the next end step.

When Horn of Seasons enters, search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equipped creature gets +3/+0.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Whenever you cast a noncreature spell, any number of target creatures you control get +1/+1 until end of turn.
Whenever a creature you control deals an amount of combat damage exactly equal to its mana value to a player or planeswalker, draw a card.

Tap an untapped Desert you control: Hostile Atmosphere deals 1 damage to any target.

Hostile Habitat deals 2 damage to each creature.
Leitmotif (If you cast this spell from your hand, exile it as it resolves. When you next cast a spell that shares a color with this card, you may cast this from exile without paying its mana cost.)

Flash
When Hostile Takeover enters, you may counter target noncreature spell.
At the beginning of your upkeep, you may put a progress counter on a Project you control.

Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
Whenever a creature you control becomes renowned, scry 1.

Target player creates two 1/1 white Spirit creature tokens with flying.
Fabled {3}{W}{W} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that player.)

When Howler Sellout enters, for each creature that died this turn, post a bounty on up to one target creature an opponent controls. (Put a bounty counter on that creature. It has “When this creature dies, each opponent draws a card” as long as it has a bounty counter on it.)

Flying, haste
Whenever a battle you control is defeated, you may return Huma of Glory from your graveyard to the battlefield.

Choose one —
• Destroy target artifact or enchantment.
• Target creature you control deals damage equal to its power to another target creature.

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you attack, add a quest counter.
1, 2 — Upgrade target creature you control. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Deathtouch
3 — Target attacking creature fights up to one other target creature.
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