msem-instigator

Whenever Arisen Rider attacks, creatures your opponents control get -1/-1 until end of turn.
If Arisen Rider or another creature or planeswalker would die, exile it instead.

Trample
Whenever Arisen Tyrant attacks, mill three cards, then you may exile a card from your graveyard. You may cast a copy of the exiled card without paying its mana cost if the spell's mana value is 3 or less.
If Arisen Tyrant would die, exile it instead.

Target creature gets +1/+1 until end of turn. Untap that creature.
Fabled {2}{W} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that creature.)

Creatures you control get +1/+1 until end of turn. You gain 3 life.
Memento {4}{W}{W} (You may cast this from your graveyard for {4}{W}{W}. If you do, put it onto the battlefield transformed after it resolves. Exile it if it would leave the battlefield or not resolve.)

Enchant player
Enchanted player may play an additional land on each of their turns.
Enchanted player may play lands from their graveyard.

When Asham's Path enters, you gain 8 life.
{1}{W}{W}: Transform Asham's Path. Activate only if your fealty to Plains is five or greater.

Indestructible
Asham, God of Morality's power is equal to your life total.
Creatures you don't control have base power 1.

Ashela, the Russet Grove enters tapped.
{T}: Add {C}.
{T}, Pay 1 life: Add {R}, {G} or {W}.
{3}, {T}: Return Ashela to its owner's hand.

{B}: Remove a counter from target permanent.
{3}{B}: Move a counter from target permanent onto Ashfeaster Ghouls. Ashfeaster Ghouls can't be blocked this turn.

When you cast your third noncreature spell each turn, transform Aspiring Rascals.

Creatures with power greater than Aspiring Recluse's can't block it.
Whenever Aspiring Recluse deals combat damage to a player, you may pay {2}. If you do, transform it.

Flying, hexproof
At the beginning of your end step, put an exiled card with an ancestry counter on it on the bottom of its owner's library, then scry 2. If there is exactly one card exiled with an ancestry counter on it, transform Atieh.

Menace
Whenever Auros, Flame-Cursed attacks, it deals 3 damage to each opponent.

Autumn Ward's power and toughness are each equal to the number of creature cards in your graveyard.
Unveil {2}{B}{G} ({2}{B}{G}: Transform this. Unveil only as a sorcery.)

When Bal's Descent enters, each player sacrifices a creature, discards two cards, and mills three cards.
{1}{B}{B}: Transform Bal's Descent. Activate only if your fealty to Swamps is five or greater.

Indestructible
You may play cards from your graveyard.
If you would draw one or more cards, mill that many cards instead.
If a card would be put into your graveyard from anywhere other than your library, exile it instead.

Deathtouch
Whenever a creature dealt damage by Barbed Beast this turn dies, transform Barbed Beast.

Vigilance, deathtouch
Whenever a creature dealt damage by Barbed Bruiser this turn dies, draw a card.

Whenever Barker Duelist becomes blocked, defending player loses 1 life.
Unveil {3}{B}{R} ({3}{B}{R}: Transform this. Unveil only as a sorcery.)

Flying
Chosen one ({W}{U}{B}{R}{G}: Transform this permanent.)

At the beginning of your upkeep, Bauble of Infinites deals 2 damage to each opponent and you gain 2 life.

(Transform this if it's not attached to a creature. Pay {1}{U} as a sorcery to unattach it.)
Enchant creature you control
Bay-Bandit's Snapper's rider gets +1/+2.
Whenever Bay-Bandit's Snapper's rider deals combat damage to a player, you draw two cards.

Whenever you cast an instant or sorcery spell, each opponent loses 1 life and Beast of Pestilence gets +1/+1 until end of turn.

Whenever Beatrice's Dodger attacks, create a 1/1 black and red Human Rogue creature token that's tapped and attacking.
{3}{B}{R}: Return Beatrice's Dodger from your graveyard to the battlefield
tapped and transformed.

(Transform this if it's not attached to a creature. Pay {2}{B}{B} as a sorcery to unattach it.)
Enchant creature you control
Belmord Blood-Coach's rider gets +3/+3 and has deathtouch.
Whenever Belmord Blood-Coach's rider attacks, you may return target creature card with mana value less than its rider's power from your graveyard to the battlefield tapped.