msem-instigator

Tithe (As you cast this spell, you may tap three artifacts and/or creatures you control.)
Return target creature or planeswalker card from your graveyard to your hand. If this spell's tithe was paid, return that card to the battlefield instead.

{1}, {T}: Tap target creature.

When Wretched Spawn enters, you may return target permanent to its owner's hand. If you do, that player discards a card.
Unearth {4}{U}{B} ({4}{U}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)

Whenever a creature attacks you or a planeswalker you control, that creature's controller mills a card.

Whenever Rustshell Mantis is dealt damage, put that many +1/+1 counters on it. (It must survive the damage to get the counters.)

{U}: Aqueous Treader gets +1/-1 until end of turn.
{U}: Aqueous Treader gets -1/+1 until end of turn.

Flying
Whenever Naiala's Guide deals combat damage to a player, draw a card, then discard a card.

Scry 2, then draw two cards. You gain 2 life.
Monument {2}{W}{U} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)

Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{3}{R}{W}: Creatures you control gain flying and haste until end of turn.

Flash
When Ascetic of Imbalance enters, draw two cards, then discard two cards. If you discarded two cards that don't share a type, Ascetic of Imbalance deals 2 damage to any target.

({T}: Add {G} or {W}.)
As Ruptured Meadow enters, you may pay {1}. If you don't, Ruptured Meadow enters tapped.

{1}, Sacrifice Ruinous Proselyte: Destroy target artifact or nonbasic land.

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Flying
Dragon spells and Adventure spells you cast cost {1} less to cast.

Menace
As long as Balefire Harbinger is attacking, creatures in its pack can't be blocked unless defending player pays {1} and 1 life for each creature they control that's blocking one of those creatures. (Two or more creatures you control with equal power are in a pack.)

Flash
Reach
Whenever Mattia enters or becomes tapped, put a +1/+1 counter on target creature you control.
{2}{G}, {T}: Target creature must be blocked this turn if able. Activate only as a sorcery.

{T}: Add {G} or {U}.
{T}, Sacrifice Sigil of Creation: Add {G}{U}.

At the beginning of your end step, put a creature card that's exiled with this enchantment onto the battlefield under your control. That creature becomes a 1/1 Spirit creature in addition to its other types and gains flying and “If this creature would die, put it on the bottom of its owner's library instead.”

Masked Impersonator can't be blocked.
Art of war — At the beginning of your end step, if Masked Impersonator dealt damage to an opponent this turn, you may have it become a copy of target creature you control except it has this ability.

Reach
{T}: Add one mana of any color. Spend this mana only to cast an Azra or Demon spell, and that spell can't be countered.

Target creature gets -2/-2 until end of turn. When that creature dies this turn, create a tapped 2/2 black Zombie creature token.

Menace
When Graygulch Outcast dies, each opponent loses 3 life.

Flying
Civilized — Whenever Fakadeh's Anointed deals combat damage to an opponent, if you control an artifact, a creature, and an enchantment, you may return target permanent card with mana value 3 or less from your graveyard to your hand.

Flying
Long-Finned Skywhale can block only creatures with flying.

Trample
Whenever Forthright Wrecker deals combat damage to a player or noncreature permanent, it deals that much damage to each other planeswalker controlled by defending player and each other battle protected by defending player.