msem-instigator

{T}: Add one mana of any color. When you spend this mana to cast a spell with mana value 5 or greater, put two +1/+1 counters on Herald of the New Divinity.

You may cast Heralds of Shikai from your graveyard as long as a creature an opponent controls died this turn.

Put a +1/+1 counter on target creature you control. Prevent all damage that would be dealt to that creature this turn.

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

At the beginning of your upkeep, nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)

(Transform this if it's not attached to a creature. Pay {4}{G} as a sorcery to unattach it.)
Enchant creature you control
Herdstrider's rider gets +1/+1 for each land you control and has trample.
Whenever Herdstrider's rider attacks, create an X/X green Elephant creature token with trample that's tapped and attacking, where X is that creature's power. Exile that token at the end of combat.

Heretic's Home enters tapped.
{T}: Add {R} or {G}.
When Heretic's Home enters, you may put a loyalty counter on a planeswalker you control.

When Heretic's Vow enters, create two 1/1 white Cleric creature tokens with lifelink.
Once each turn, when you gain life, you may put a +1/+1 counter on target creature you control.

When this creature enters, look at target opponent's hand. You may exile a nonland card from it. For as long as that card remains exiled, its owner may play it. A spell cast this way costs {2} more to cast.
Arise {2}{W}{W} ({2}{W}{W}, Exile this from your graveyard as a sorcery: Create a black token copy of it that's also a Zombie and can't block.)

{1}{U}, {T}: Reveal the top card of your library. If it doesn't share a color with Heretical Seer, put it into your hand.

{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.

For each color among nontoken permanents you control, add one mana of that color.

When Hermetic Fisher dies, you may return target creature to its owner's hand.

Enchant creature or planeswalker
Enchanted permanent has base power 0 and loses all abilities.

Hexproof, vigilance, lifelink

Target player sacrifices any number of lands. That player searches their library for up to that many land cards, puts them onto the battlefield tapped, then shuffles.
Fabled {5}{G}{G} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that player.)

Deathtouch
Whenever a storied permanent you control enters, remove up to two counters from target creature or planeswalker an opponent controls. (Enchantments and legendary permanents are storied.)

Whenever Hero of Aer attacks, it gets +2/+1 until end of turn.

You may have Hero of Shengin Province assign its combat damage as though it weren't blocked.
{2}{G}: Until end of turn, you may have creatures you control assign combat damage as though they weren't blocked. Activate only if Hero of Shengin Province is in your graveyard.

Vigilance
Concord — {G}: Hero of the Stained Blade gets +2/+2 and gains trample until end of turn. Activate only if there are four or more card types among permanents you control and only once each turn.

Equipped creature gets +3/+1 and has haste.
Equip Soldier or Warrior {1}
Equip {4}

Whenever Hero's Henchman attacks, another target creature you control gets +1/+1 until end of turn.

Search your library for a basic land card and put it onto the battlefield, then shuffle. 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.”)

Flying
Whenever Heroes of Wars Past attacks, attacking Human creatures get +1/+1 and gain flying until end of turn.

Colossal 2—{6}{W}{W} (You may cast this for its colossal cost to have it enter with two +1/+1 counters; or pay {6}{W}{W} as a sorcery: Put two +1/+1 counters on it if it has none.)
When Heroes' Adversary's colossal ability puts one or more counters on it, exile target creature an opponent controls until Heroes' Adversary leaves the battlefield.