msem-instigator

Whenever Hedge Dashers attacks, if you control a permanent with a counter on it, Hedge Dashers gets +1/+1 and gains trample until end of turn.

Trial 3 (As you cast this spell, an opponent of your choice may pay 3 life. If they don't, they fail the trial.)
When Heedless Adversary enters, you may have it deal 3 damage to target creature if that creature's controller failed the trial.

Whenever Heedless Astronaut attacks, it gets +2/+0 and gains indestructible until end of turn.

When Heedless Lovers enters, you may return target Citizen card from your graveyard to your hand.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Equipped creature gets +1/+1 for each card in your hand.
Equip {3}

Lifelink
Embellish {2}{B} (If you cast this spell for {2}{B}, create a 1/1 blue Thopter artifact creature token with flying when it enters.)

This spell costs {2} less to cast if you sacrificed a Clue this turn.
Target player discards two cards.

Trample
Whenever Heir to the Old Bonds becomes the target of a spell or ability you control for the first time each turn, put a +1/+1 counter on it.

At the beginning of combat on your turn, you may attach any number of Equipment you control to target creature you control.

When Heirloom Seeker enters, you may search your library for an Equipment card, reveal it, then shuffle and put that card on top of it.
Heirloom Seeker has first strike as long as it's equipped.

Rogues and Pirates you control have haste.
Whenever one or more creatures you control deal combat damage to a player, exile the top card of your library. You may play that card this turn.

At the beginning of each combat, up to one target creature can't attack or block this turn.

Untap target creature. It gets +1/+3 until end of turn.

When Helicos Aberration enters, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)

When Helicos Octopus enters, scry 1. If an opponent is cursed, scry 3 instead.

When Helicos-Drowned Captain enters, create a black Aura Curse enchantment token named Marked for Death attached to target player. The token has enchant player and “At the beginning of enchanted player's upkeep, that player loses 1 life.”

Enchant creature you control
When Heliod's Benefaction enters, scry 2.
Enchanted creature gets +1/+1 and has lifelink.

Whenever you scry, you gain life equal to the number of cards looked at while scrying this way.

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.)

Whenever you cast a noncreature spell, you may put a progress counter on Hellbent Speed.
[PROGRESS 2+] Noncreature spells you cast cost {1} less to cast. This effect can't reduce the amount of mana a spell costs to cast to less than one mana.
[PROGRESS 6+] Whenever you cast a noncreature spell, draw a card.

This spell costs {X} less to cast, where X is your devotion to green. (Each {G} in the mana costs of permanents you control counts toward your devotion to green.)
Trample

Menace
{1}{B}{R}: Creatures you control get +1/+0 until end of turn.

Hellkite's Decree deals 3 damage divided as you choose among one, two, or three target creatures and/or planeswalkers.
Cycling {2} ({2}, Discard this card: Draw a card.)

{T}: Add {C}.
{T}, Reappropriate: Add {B} or {R}. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)