msem-instigator

Flying
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Honorable Mentor mentors a creature, that creature and Honorable Mentor each gain first strike until end of turn.

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.

{T}: Untap another target enchanted creature you control. You may attach target Aura attached to that creature to another creature you control. Activate only as a sorcery.

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

This spell costs {1} less to cast for each +1/+1 counter among creatures you control.
Hoof Cliff Heartminer enters with four +1/+1 counters on it.
Whenever Hoof Cliff Heartminer or another creature you control leaves the battlefield, you may put its +1/+1 counters on another target creature you control.

Vigilance
Menagerie — When Hoof Cliff Trihorn enters, if there are five or more creature types among creatures you control, you may search your library for a card named Hoof Cliff Trihorn, reveal it, put it into your hand, then shuffle.

Audition for white. If you create a Role this way, untap the creature it enchants. (Create a 1/1 Construct Actor creature token, a Scout Role giving 2/3 and vigilance, or a Cleric Role giving 2/2 and lifelink. Roles replace older ones.)

Create two 1/1 white Cleric creature tokens with lifelink.

Flying
Morph {4}{W} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When you turn Hopebringer Cherub face up, creatures you control get +1/+1 until end of turn.

Lifelink
Whenever you gain life, you may transform Hopeful Caretaker. If you don't, put a +1/+1 counter on it.

Hopeful Healer gets +1/+1 and has lifelink as long as you are glorious. (You are glorious as long as you have a glory counter.)

When Horizon Treader enters, exile target enchantment you control, then return that card to the battlefield under your control.

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.

Alpha (You may have this creature enter with a +1/+1 counter on it. If you do, it becomes alpha and can only attack alone.)
Lifelink

Target blocking creature gets +7/+7 and gains indestructible until end of turn. You get a glory counter. (You lose glory counters before life. A player with ten or more glory counters wins the game.)

Advance {2}{W} (Cast this for {2}{W} to advance it as it enters. {2}{W}: Advance this as a sorcery.)
Whenever Hoverstepper advances, target creature gets +1/+1 and gains flying until end of turn.

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.)

Advance {3}{W} (Cast this for {3}{W} to advance it as it enters. {3}{W}: Advance this as a sorcery.)
Whenever Hrexa Enforcer advances, put a +1/+1 counter on it.

Other untapped creatures you control have indestructible.
{2}{G}{W}: Target creature gains vigilance until end of turn.

Humble Fieldhand gets +1/+0 and has vigilance as long as you control an Equipment.

When Humble Tamer enters, create a 1/1 white Griffin creature token with flying.

Enchant player
For each 1 life enchanted player would gain, you gain 1 life instead unless that player pays {1}.

First strike
When Hunted Haunt dies, create a 1/1 black Scout creature token.

Rapport — Whenever Hunting Hound and at least one other creature you control become tapped, Hunting Hound gets +2/+0 until end of turn.

Vigilance
When Huolin Sanctifier dies, if it was in a pack, create a 2/1 black Spirit creature token with “This creature can't block.” (Two or more creatures you control with equal power are in a pack.)