msem-instigator

When March of the Unhallowed enters, mill three cards, then return a creature card with mana value 3 or less from your graveyard to the battlefield.
Whenever you attack with three or more creatures, each opponent loses 1 and you gain 1 life.

{T}: Add {C}.
{T}, Exile two cards from your graveyard: Add {R} or {G}.

Once each turn, when you foretell a card or cast a foretold spell, you may create a tapped Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Whenever a creature enters under an opponent's control, you may pay 2 life. If you do, draw a card.

You may exert Heavenly Bull as it attacks. When you do, it gains indestructible until end of turn. (An exerted creature won't untap during your next untap step.)
{3}{G}{W}: Destroy all nonland permanents with mana value 3 or less. Activate only if Heavenly Bull is attacking and only once.

Create a 1/1 blue Bird creature token with flying. (Cast a copy of this spell once while this creature is on the battlefield.)

Haste
Madness {3}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

When Sha'Iv Cagemage enters, adjudicate. (Create a white Aura enchantment token with enchant creature and “Sacrifice this token: Untap enchanted creature” attached to target creature.)
Whenever an Aura you control enters, you may tap target creature.

({T}: Add {G} or {W}.)
Timeless Shrine enters tapped.
{1}, {T}: Add {G}{G} or {W}{W}.

Flash
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter
on Petty Thief.
Surpass {5}{U} ({5}{U}: Transform this. This costs {1} less to activate for each counter on
it. Activate only as a sorcery.)

Lifelink
Effigy of Morality gets +1/+1 as long as your fealty to Plains is four or greater. (Each Plains you control counts towards your fealty to Plains.)

{1}, {T}, Sacrifice a creature: Search your library for a creature card with mana value 1, put it onto the battlefield, then shuffle. Activate only as a sorcery.

Exile target creature with mana value 2 or less.

Indestructible
As long as your devotion to green and white is less than seven, Karametra isn't a creature.
You may play an additional land on each of your turns.
As you begin searching your library, you may reveal a basic land card from your library and put it into your hand.

First strike, menace, lifelink
{X}{2}{B}, Discard Wihtfyr: Create a tapped 0/0 Skeleton Army creature token with “This creature gets +1/+1 for each creature card in your graveyard.” For each of up to X Armies, put your choice of a first strike, lifelink, or menace counter on that Army.

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you cast your second spell each turn, add a quest counter.
1 — Exile the top card of your library. You may play that card until the end of your next turn.
2 — The second spell you cast during your next turn cost {1} less to cast.
3 — You may cast target instant or sorcery card from your graveyard this turn. When you do, copy it. You may choose new targets for the copy.

Target player discards two cards. Then exile that player's graveyard.

Reveal the bottom four cards of your library. Choose up to one permanent card with mana value 3 or less from among them and put it onto the battlefield. Put the rest on the bottom of your library in any order.

Choose two —
• After the first postcombat main phase this turn, there's an additional combat phase followed by an additional main phase. Creatures you control gain vigilance until end of turn.
• Creatures you control gain indestructible until end of turn.
• Creatures you control gain lifelink until end of turn.
• Creatures you control get +2/+0 until end of turn.

Reach
Wanderlust — Voliv Skyhunter gets +2/+0 and has first strike as long as you control four or more differently named lands.

Once each turn, you may pay {U} rather than pay the mana cost for a blue spell you cast.

Flying
Whenever Hoff's Scout deals combat damage to a player, you may scry 1.

When Shadowstrider dies, create a 2/2 colorless Spirit creature token.

When Graygulch Howler dies, you gain 1 life for each Spirit you control.

Runewart Hog has hexproof as long as it has a +1/+1 counter on it.