msem-instigator

{3}{G}: Elder Rootwallas gets +4/+2 until end of turn. Activate only once each turn.

Whenever Fireheart Centaur attacks, you may pay {2}{R}. If you do, it gets +1/+0 until end of turn for each Centaur you control.

When Gold Farmer enters, create a Treasure token.

{T}: Add {G}.
Dominance — {T}: Add {G}{G}. Activate only if you control the creature with the greatest power or tied for the greatest power.

{T}: Add one mana of color.
{3}{G}, {T}: Audition for green. Activate only as a sorcery. (Create a 1/1 Construct Actor creature token, a Scout Role giving 2/3 and vigilance, or a Warrior Role giving 3/2 and trample. Roles replace older ones.)

Defender (This creature can't attack.)
When Naturebound Druid enters, you may search your library for a basic land card, reveal it, then shuffle and put that card on top.

Other untapped creatures have hexproof.
Whenever a creature attacks you, put a +1/+1 counter on a creature you control.

{T}: Add {G}. If there are three or more creature cards in your graveyard, add {G}{G} instead.

Defender
When Wall of Ivy enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

Whenever an enchantment you control enters, draw a card.

Guide to the Wayward enters with a +1/+1 counter on it.
{1}{W/U}, {T}: Permutate. (You may remove a counter from a creature you control. If you do, put two +1/+1 counters on a different creature you control.)

{T}, Sacrifice a permanent: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Ve'aja, the First Bloodline's power is equal to the number of Clerics you control.
Whenever another nontoken creature you control dies, you lose X life and create X 1/1 black Cleric creature tokens, where X is that creature's power.

Whenever a creature an opponent controls becomes blocked, put a -1/-1 counter on that creature.

Defender
Whenever you cast an instant or sorcery spell, you may untap Almgrove Sentinel.
{T}: Almgrove Sentinel deals 1 damage to any target.

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

Creatures with defender you control can attack as though they didn't have defender.
Each creature you control assigns combat damage equal to its toughness rather than its power.

When Artificial Wayfinder enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

{T}: Add {C}. You gain 1 life.
Pristine Frame gets +2/+2 and has flying as long as you have 25 or more life.

Flash
{1}, {T}: Scry 1.

Slaughterkeg can't attack or block.
While an opponent is choosing targets as part of casting a spell they control or activating an ability they control, that player must choose at least Slaughterkeg if able.
When Slaughterkeg dies, draw a card.

Fox of the Fallen Forest gets +4/+0 as long as you control a legendary creature.

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever Protective Patron extorts a creature spell, that creature gains indestructible until your next turn.

Defender (This creature can't attack.)
{W}, {T}: You gain 1 life.