msem-instigator

This spell can't be countered.
Vigilance
Noncreature spells cost {1} more to cast.

Other Angels and Nephilim you control get +1/+1.
As long as you control three or more other Angels and/or Nephilim, Herald of Atieh gets +1/+1 and has flying.

Whenever another nontoken creature you control dies, create a 1/1 green Saproling creature token.
{B}{G}, {T}, Sacrifice a creature: Return target permanent card from your graveyard to your hand.

Other Azra and Demons you control get +1/+1.
As long as you control three or more other Azra and/or Demons, Herald of Tamaak gets +1/+1 and has flying.

Haste
Herald of Unity's power is equal to the number of creatures you control.

Trample, haste
Herald of Untold Riches gets +1/+1 for each color among other spells you've cast this turn.

Rapport — Whenever Herald of the Hunt and at least one other creature you control become tapped, nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)

When Herd Matron enters, distribute two +1/+1 counters among one or two target creatures you control.

When Here Forever enters, exile target creature or planeswalker until Here Forever leaves the battlefield.
At the beginning of your upkeep, the owner of the exiled card loses 1 life.

{B}{R}, {T}, Sacrifice Heretical Soulshifter: Return target creature card from your graveyard to the battlefield. It gains haste until end of turn. Activate only as a sorcery.

Hexproof, vigilance, lifelink

When Heroic Aspiration enters, you may search your library for a creature card with an Adventure, reveal it, put it into your hand, then shuffle.
At the beginning of your end step, if you cast both a creature spell and a noncreature spell this turn, Heroic Aspiration deals 2 damage to each opponent and you gain 2 life.

Reach
As long as you control an artifact or an enchantment, Heron's Grace Patrol gets +1/+1 and has vigilance.
{2}{G}{W}, {T}: Mill three cards. You may return a permanent card milled this way to your hand.

[+1]: Add {G}{U}{R}. Spend this mana only to cast creature spells.
[–2]: Reveal the top card of your library. If it's a creature card that costs less than the last spell you cast this turn, you may put it onto the battlefield. Otherwise, draw a card.
[–7]: Target creature becomes a legendary 20/20 green creature named Illusion of Kaur with hexproof and trample until end of turn.

Flash
When Hexfang Ascetic enters, return target spell to its owner's hand.

Whenever you draw a card, put a +1/+1 counter on Highborn Meditant.

Wanderlust — Whenever Highwild Survivalist attacks, add {R} or {G}. If you control four or more differently named lands, add {R}{G} instead. Until end of turn, you don't lose mana added this way as steps and phases end.

When Hila Okunos enters, look at the top six cards of your library. You may reveal an Aura or Aurashaper card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Whenever another nontoken Aura or Aurashaper you control enters, create a token that's a copy of it.

When Hired Kalak enters, put target card from your graveyard on top of your library.

Whenever a creature dies, exile it.
Hiroto Jaakuna has all activated abilities of creature cards exiled with Hiroto Jaakuna.

If a permanent with spirited entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

When Historiamancer enters, return target instant or sorcery card from your graveyard to your hand.

First mate—Each nonland card in your starting deck has the same name as exactly one other card in your starting deck. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Vigilance
Whenever you cast a spell with the same name as a card in your graveyard, draw a card.

When Hold Captive enters, exile another target nonland permanent until Hold Captive leaves the battlefield.
When Hold Captive enters, recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)

Hollow Queen can't be blocked by tokens.
Whenever Hollow Queen deals combat damage to a player or planeswalker, you may remove a counter from a permanent you control. If you do, put a +1/+1 counter on target creature you control.