msem-instigator

At the beginning of combat on your turn, gain control of another target permanent until end of turn. Untap that permanent. It gains haste until end of turn.
Fleeting {2}{R}{R} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

Trample
When Magmatic Ravager enters, two target lands you control don't untap during your next untap step.

Assault {2}{R} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Monstrous Hila assaults, it deals 3 damage to any target.

Trial 6 (As you cast this spell, an opponent of your choice may pay 6 life. If they don't, they fail the trial.)
Flying
When Reckoner of Man enters, if the trial was failed, it deals 3 damage to each creature you don't control.

Flying
Whenever Scavenging Hilakites attacks, you may sacrifice another creature. When you do, Scavenging Hilakites deals damage equal to the sacrificed creature's power to any target.

Flying
Lands you control have “{T}: Add {R}{R}. This land deals 2 damage to you.”
{R}{R}{R}{R}{R}{R}: Shuffle your library, then exile the top three cards. You may cast one of them without paying its mana cost.

Flying, haste
Volcano Tyrant enters with a first strike counter on it.
{2}{R}, Remove a first strike counter from Volcano Tyrant: Double its power and it gains trample until end of turn.

Vigilance, reach
As a noncreature spell resolves, exile it instead of putting it anywhere else.

Ward {3}

Vigilance, trample
Whenever another Horror you control enters, choose one —
• Destroy target artifact or enchantment.
• You gain 4 life.
• Apex Abomination fights another target creature.

This spell costs {1} less to cast for each differently named land you control.
Reach, trample

Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Vigilance
Resolute — Canopy Stomper can't be blocked by creatures with power 2 or less as long as Canopy Stomper's power is greater than its base power.

Creatures you control get +4/+4 and gain trample until end of turn.
Coalesce {8}{G}{G} (You may cast this from your graveyard for {8}{G}{G}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
Trample

Vigilance, reach
When DL-19 Reject enters, target creature you control gets +2/+2 until end of turn.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature an opponent controls dies, create a Food token. (It's an artifact with “{2}, {T}, Sacrifice this artifact: You gain 3 life.”)

Assault {1}{G} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Dune Tromper assaults, it gains trample until end of turn.

Whenever Encouraging Bulwark attacks, you may put a +1/+1 counter on each creature you control that's enchanted and/or has one or more counters on it.

This spell costs {1} less to cast for each creature card in your graveyard.

Reach, trample
Improve {1}{B/G} ({1}{B/G}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
Whenever one or more +1/+1 counters are put on Gorganith, Ruin Maw, you may search your library and/or graveyard for a creature card with mana value equal to or less than the number of +1/+1 counters on Gorganith and put it onto the battlefield. If you search your library this way, shuffle.

{4}{G}{G}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)
When Grizzly Matriarch becomes monstrous, destroy target noncreature permanent an opponent controls.

Trample
Whenever Living Archipelago enters or attacks, up to two target lands you control voyage. (If they aren't being targeted by another spell or ability, they phase out.)
Whenever a land you control phases in, you may create a tapped token that's a copy of that land.

Trample
Augmented — When Lonely Giant enters, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, put two +1/+1 counters on it.

Trample
When Nanowrought Progenitor enters, draw a card for each creature you control with two or more card types.

Deathtouch
When Nyx-Eater Basilisk enters, exile up to one target enchantment.
{2}{G}, Discard Nyx-Eater Basilisk: Exile target enchantment.