msem-instigator

While an opponent is choosing targets as part of casting a spell they control or activating an ability they control, that player must choose at least one Flagbearer on the battlefield if able.
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.)

Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
Whenever a creature you control blocks or becomes blocked, it gets +1/+1 until end of turn for each +1/+1 counter on it.

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.

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.

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.

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.)

Flying, vigilance

Lifelink
When Hyctaleon's Vanguard enters, look at the top six cards of your library. You may put a Soldier card with lesser mana value from among them onto the battlefield. Put the rest on the bottom of your library in a random order.
Other Soldiers you control get +1/+1.