msem-instigator

Trample

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.)

Flying, haste
Whenever Grieving Revenant attacks, it deals 1 damage to each other creature you control.

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.”

Sacrifice another creature: Grindlesnap gets +3/+2 and gains trample until end of turn if that creature was a Crocodile. Otherwise, it gets +1/+1 until end of turn.
Whenever Grindlesnap is dealt combat damage, create a 3/2 green Crocodile creature token with trample.

Trample
At the beginning of each combat, you may have Grisly Offering deal 3 damage to target creature you control. If you do, Grisly Offering gets +3/+0 until end of turn.

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

Grizzled Den enters tapped.
{T}: Add {R} or {G}.
{3}{R}{G}: Until end of turn, Grizzled Den becomes a Bear creature with trample in addition to its other types.
Scavenge {4}{R}{G}

When Grotto Scarab enters, create two 1/1 green Insect creature tokens for each creature you controlled that died this turn.

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

When Guardian of Lost Truths enters, if a library has twenty or fewer cards left in it, draw two cards. Otherwise, target player mills five cards.

Menace
Death knell — Put a +1/+1 counter on Guiltless Wraith. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)

As an additional cost to cast this spell, return any number of creatures you control to their owner's hands. This spell costs {1} less to cast for each creature returned this way.
Whenever Gwynsivir attacks, if a creature entering causes a triggered ability of a permanent you control to trigger this turn, that ability triggers an additional time.

Reach, trample
{1}{G}: You may remove a counter from a creature you control. If you do, tap that creature and it gains indestructible until end of turn.

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.

Flying
If a source you control would deal noncombat damage to a permanent or player, you may have it deal damage equal to Hadak's power instead.

Hafiq the Wise has hexproof as long as you've cast a spell this turn.
{U}, Discard a card with mana value X: Counter target spell with mana value X.
{U}, Sacrifice another permanent with mana value X: Return target instant or sorcery card with mana value X from your graveyard to your hand.

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

Flying, trample
Whenever Hao'Tai, the Ancient One deals combat damage to a player, exile the top four cards of that player's library. Until end of turn, you may cast instant, sorcery, and creature cards from among those exiled cards, and you may spend mana as though it were mana of any color to cast them.

Trample
As an additional cost to cast creature spells, you may sacrifice a permanent. If you do, that spell costs {2} less to cast and that creature enters with an additional +1/+1 counter on it.

This spell costs {X} less to cast, where X is the number of Dwarves and Elves you control.
Trample, haste
Whenever Harl and Finn attacks, other creatures you control get +1/+1 and gain trample until end of turn.

When Harpooned Bubbledomer enters, mill four cards.
Harpooned Bubbledomer gets +2/+0 and has menace as long as there are four or more card types among cards in your graveyard.

Whenever you cast an instant or sorcery spell from your hand, put that card onto the battlefield face down as a 2/2 creature instead of putting it into your graveyard as it resolves.
Whenever a face-down creature you control deals combat damage to an opponent, you may exile it. If you do, you may cast it without paying its mana cost.

When Hatewracked Explorer enters, you may sacrifice an artifact or creature. If you do, crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)
{4}{B}{R}, Sacrifice an artifact or creature: Destroy target creature if it was dealt damage this turn.

Whenever you cast a black spell, you may exile target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.
Whenever you cast a red spell, you may have Haunted Sunseeker deal 1 damage to each creature.