msem-instigator

Disgraced 5 (This enters with five -1/-1 counters. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
Prevent all combat damage that would be dealt to Heir Unapparent.

Destroy target artifact or land. If a land was destroyed this way, its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

Whenever Herald of Purity is dealt damage, it deals that much damage to any target.
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.)

Lifelink
When Herald of Royalty enters, creatures you control get +1/+1 and gain vigilance until end of turn.

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

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

When you attain Hopeless Lanonshee, create two 1/1 black Construct artifact creature tokens.
Whenever a creature dies, each opponent loses 1 life and you gain 1 life.

Whenever Hopeless Romantic or another creature you control dies, each opponent loses 1 life.
Attain {3}{B} ({3}{B}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

{T}: Hotblooded Sorcerer deals 1 damage to target player or planeswalker.
Attain {3}{R} ({3}{R}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Choose one —
• Exile target artifact.
• Target player exiles two artifacts they control with mana value 0.

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

Enchant creature
As Hunter's Distinction enters, you may tap enchanted creature if it's untapped. When you do, put three -1/-1 counters on target creature with flying.
Enchanted creature gets +3/+2 and has reach.

Reach
Deploy 3 (As this enters, you may tap any number of other creatures you control with total power 3 or more.)
When Hunting Company enters deployed, destroy target creature with flying.

Creatures you control have “{T}: Add {C} or one mana of any of this creature's colors.”
Attain {5}{G} ({5}{G}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

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.

Hexproof, indestructible
You don't lose the game for having 0 or less life.
For each 1 life you would lose while you have 0 or less life, instead put a -1/-1 counter on a creature you control with toughness 1 or greater.

Defender
When Immured Fiend enters, target opponent discards two cards.

Enchant creature
When Imperative Blessing enters, draw a card.
Enchanted creature gets +2/+2.

Draw three cards.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

When Imperfect Stone enters, mill three cards.
{T}: Add one mana of any color.

{T}: Add {C}.
{4}, {T}, Put a -1/-1 counter on a creature you control: Draw a card.

First strike
When Imperial Dragoon enters, target creature gets +2/+0 until end of turn.

This spell costs {1} less to cast for each tapped creature you control.
Whenever Incarnation of Enmity attacks, each other attacking creature gets +1/+0 until end of turn.

Disgraced 1 (This enters with a -1/-1 counter. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
Whenever Indebted Burglar becomes blocked, defending player loses 1 life.

Target creature you control deals damage equal to its power to target creature you don't control.
Create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)