msem-instigator

Trample
At the beginning of your upkeep, if your fealty to Forests is five or greater, transform Hand of the Harvest. (Each Forest you control counts towards your fealty to Forests.)

Menace, haste
Other Centaurs you control get +1/+0.

Flash
When Lizaveth's Surveyor enters, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
Lizaveth's Surveyor's power is equal to the number of artifacts you control.

Adorned — Mercenary Lancer gets +2/+2 as long as it's equipped and/or enchanted.

Whenever a creature you control becomes tapped, exile the bottom card of your library. You may put it on top of your library. If you don't, Flames of the Forge deals 1 damage to target opponent or planeswalker.

Menace (This creature can't be blocked except by two or more creatures.)

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.

Doomsday Horde enters tapped unless it was foreshadowed.
When Doomsday Horde dies, search your library for a card, put it into your hand, then shuffle.
Foreshadow {3}{B}{B}{B} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

{2}{W}: Prevent all damage that would be dealt to and dealt by Suncaller Nymph this turn.

At the beginning of each upkeep, if it's an extra turn, end the turn.
If a player would search a library, that player searches the top four cards of that library instead.

Trample
When Sahra's Crusher enters, judge another target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)

As an additional cost to cast this spell, sacrifice a creature.
Destroy target creature.

{2}{B/G}: Return Silthway Scuttler from your graveyard to your hand.
{2}{B/G}, Exile Silthway Scuttler from your graveyard: Put two +1/+1 counters on target creature.

When Leech-Ridden Corpse dies, each opponent loses 1 life and you gain 1 life.

As an additional cost to cast Reunite with Nature, sacrifice X creatures.
Create X plus one 3/1 red and green Elemental Horror creature tokens with haste and trample.

Flying, menace, haste
Twisted Archangel has indestructible as long as an opponent has four or more cards in hand.

Flying
Glorious end — When Blinded Avenger dies, if it was tapped, destroy target creature you don't control.

Douse in Flame deals 5 damage to target creature without flying. When that creature leaves the battlefield this turn, exile its controller's graveyard.

Indestructible
As long as your devotion to red and white is less than seven, Iroas isn't a creature.
Other creatures you control have first strike.
Whenever you attack for the first time each turn, untap all other creatures you control. After this phase, there is an additional combat phase.

Whenever another creature you control enters, you gain 1 life.

{T}: Add {C}.
{1}, {T}: Add one mana of any color. When that mana is spent to cast an Adventure spell, scry 1.

Whenever one or more creature cards leave your graveyard, Hadik's Cohort deals 2 damage to target opponent.

When Scion of Sarrithaz enters, create a 2/2 black Zombie creature token.
{2}{B}, Sacrifice a creature: Draw a card.

Flash
Prowess
When Reconstructed Adept enters, target instant or sorcery card in your graveyard gains agonize until end of turn. (You may cast it by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile that card.)

Return target creature card with power less than or equal to your fealty to Swamps from your graveyard to the battlefield. (Each Swamp you control counts towards your fealty to Swamps.)