msem-instigator

Flash
When Gravetiller enters, you may exile target creature or planeswalker card from a graveyard. If it had mana value 4 or less, you may return it to its owner's hand. Otherwise, you may shuffle it into its owner's library.
Evoke {B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

If it isn't an extra turn, take an extra turn after this one. (Cast a copy of this spell once while this creature is on the battlefield.)

Flying
When Greater Swooprat enters, creatures your opponents control get -1/-1 until end of turn.

Trample

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

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Griffin Skycaller enters, target creature you control gets +1/+1 and gains flying until end of turn.

When Grim Festivities enters or at beginning of your upkeep, you may return a creature card from your graveyard to the battlefield under your control. If you do, each opponent may return a creature card from their graveyard to their hand.

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.”

{4}{G}{G}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)
When Grizzly Matriarch becomes monstrous, destroy target noncreature permanent an opponent controls.

Archive 6
Grohl's Study's power and toughness are each equal to the number of cards in the archived library.
Whenever Grohl's Study deals combat damage to a player, you may put a card from the archived library into your hand.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Sacrifice another creature: Grotesque Defiler gains flying until end of turn.
Whenever Grotesque Defiler deals combat damage to a player, if you're in a renaissance, that player discards a card.

Menagerie — When Grotto Guardian enters, if there are five or more creature types among creatures you control, target creature you don't control gets -2/-2 until end of turn.

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.

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.

Whenever H.S.S. Demeter becomes blocked by a creature, gain control of that creature.
Whenever H.S.S. Demeter deals combat damage to a player, draw two cards.
Crew 2 (Tap any number of creatures you control with total power 2 or greater: This Vehicle becomes an artifact creature 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.

[+1]: Haide Bankbuster deals 2 damage divided as you choose among one or two targets.
[+1]: Draw two cards unless any player has Haide Bankbuster deal 3 damage to them.
[–9]: Until end of turn, gain control of all permanents target player controls and they gain haste. Untap those permanents.

Flying
When Hallowed Executioner enters, it deals 2 damage to each creature without flying.

Enchant land
Enchanted land has “{T}: Tap target creature.”

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 Hand of the Evil One enters, mill three cards. Draw a card for each Zombie card milled this way.
Unearth abilities you activate cost up to {1} less to activate.

Flying
Whenever Hao'Tai deals combat damage to a player, that player exiles the top five cards of their library and separates them into two piles. Put an ember counter on each card in the pile of your choice. You may play cards from exile with ember counters for as long as they remain exiled.