msem-instigator

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.

Enchant creature
When Hypnotic Halo enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
{2}{W}{W}, Sacrifice Hypnotic Halo: Exile enchanted creature.

{1}{W}: Artifact creatures you control get +1/+1 until end of turn. Activate only once each turn.

When Ideologize enters, exile target creature an opponent controls and each other permanent with the same name that player controls. When Ideologize is no longer on the battlefield, return a card exiled with it to the battlefield under its owner's control.

Concord — At the beginning of your upkeep, if there are four or more card types among permanents you control, you gain 1 life and create a 1/1 blue Jellyfish enchantment creature token with slipstream. (It can't be blocked as long as only creatures with slipstream are attacking.)

Search your library for an enchantment card, reveal it, put it into your hand, then shuffle.

Vigilance
Once each turn, when you cast an instant, sorcery, or Elemental spell, you may put a +1/+1 counter on Ignited Vanguard.

Target player sacrifices an attacking or blocking creature.

Vigilance
When Illari, Martyrized Tyrant enters, tap all other nonbasic permanents.
Players can't untap more than one nonbasic permanent during each of their untap steps.
When Illari dies, untap all permanents you control and you gain 5 life.

Flying
When Illuminating Archangel enters, target creature gets +X/+X and gains vigilance and first strike until end of turn, where X is the number of permanents you control that are Angels, Demons, Faeries, and/or Spirits.

Whenever Illumination Savant attacks, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Put a +1/+1 counter on each artifact creature and enchantment creature you control.

At the beginning of each opponent's end step, that player gets a poison counter unless damage was dealt this turn.

Flying
Whenever Immaculate Clouddasher attacks, up to three target creatures gain flying until end of turn.