msem-instigator

Flying, trample
When this creature transforms into Griselbrand, the Usurper, draw seven cards.

Sacrifice another creature: Grisly Rougarou deals damage equal to the sacrificed creature's power to any target.

Other creatures you control that are Knights or have Adventures get +1/+1.

{2}, Sacrifice a creature or artifact: Hadak's Guardian deals 2 damage to any target.

When Hand of Consequence enters, creatures your opponents control get -1/-1 until end of turn.
At the beginning of your upkeep, if your fealty to Swamps is five or greater, transform Hand of Consequence. (Each Swamp you control counts towards your fealty to Swamps.)

When Hand of Dominion enters, tap target creature an opponent controls. It doesn't untap during its controller's next untap step.
At the beginning of your upkeep, if your fealty to Islands is five or greater, transform Hand of Dominion. (Each Island you control counts towards your fealty to Islands.)

When Hand of Fidelity enters, creatures you control get +1/+1 until end of turn.
At the beginning of your upkeep, if your fealty to Plains is five or greater, transform Hand of Fidelity. (Each Plains you control counts towards your fealty to Plains.)

When Hand of Fury enters, it gets +2/+2 and gains haste until end of turn.
At the beginning of your upkeep, if your fealty to Mountains is five or greater, transform Hand of Fury. (Each Mountain you control counts towards your fealty to Mountains.)

Trample
At the beginning of your upkeep, if your fealty to Forests is five or greater, transform Hand of the Harvest. (Each Forest you control counts towards your fealty to Forests.)

Indestructible
Whenever Hannaru the Conqueror attacks, put a +1/+1 counter on each creature you control.

Hanweir Miscreant can't be blocked by creature tokens.
{2}{R}: Transform Hanweir Miscreant. Activate only if it's attacking.

Flying
At the beginning of your first main phase, you may put any number of land cards from your hand onto the battlefield, then draw a card for each land put onto the battlefield this way.

{W}: Target creature assigns combat damage equal to its toughness rather than its power this turn.

Whenever Haunted Prodigy attacks, you may tap target creature.
Unveil {2}{W}{U} ({2}{W}{U}: Transform this. Unveil only as a sorcery.)

Vigilance
At the beginning of your end step, if you control two or more Spirits and/or creatures with flying, transform Haunted Waif.

Whenever Haunting Maestro attacks, you may tap or untap up to two target creatures.

Flying
Whenever Havengul Banshee attacks, each creature defending player controls gets -1/-0 until end of turn.
{3}{U}: Return Havengul Banshee from your graveyard to the battlefield transformed under your control attached to target opponent. Activate only as a sorcery.

Ward—Sacrifice a permanent.
Whenever a player sacrifices a permanent, put a +1/+1 counter on Hayat, Hungering Bakhtak.
Surpass {4}{B}{G} ({4}{B}{G}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Deathtouch
Discard a card: Headless Carriage gains indestructible until end of turn. Tap it.
Ride {2}{B}{B} ({2}{B}{B}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

Flying, vigilance, deathtouch, lifelink

Lifelink

(Transform this if it's not attached to a creature. Pay {B} as a sorcery to unattach it.)
Enchant creature you control
Herald of Death's rider gets +1/+1.
Sacrifice a creature: Herald of Death's rider gets +2/+2 until end of turn.

Whenever you put a counter on another permanent you control, put a +1/+1 counter on Herald of Ruination. This ability triggers only once each turn.
Surpass {5}{G} ({5}{G}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

(Transform this if it's not attached to a creature. Pay {4}{G} as a sorcery to unattach it.)
Enchant creature you control
Herdstrider's rider gets +1/+1 for each land you control and has trample.
Whenever Herdstrider's rider attacks, create an X/X green Elephant creature token with trample that's tapped and attacking, where X is that creature's power. Exile that token at the end of combat.

Lifelink
Tap three other untapped creatures and/or artifacts you control: Transform Heroic Crusader.