msem-instigator

{1}, {T}, Pay 1 life: Put a +1/+1 counter on target creature you control.
{T}, Remove a counter from a permanent you control: Draw a card.

Flying
Spelldust Sprite gets +1/+1 as long as you control four or more creatures with flying.
If you would create a token, you may instead create a token that's a copy of Spelldust Sprite, except it doesn't have this ability.

Flying, vigilance
Whenever you attack, if you've cast a spell from a graveyard this turn, you may pay {1}{W}. If you do, put Defender of Carü Mapu from your graveyard onto the battlefield. It's attacking.

Defender
When Mnemonic Wall enters, you may return target instant or sorcery card from your graveyard to your hand.

Whenever you cast an instant or sorcery spell, target creature can't block this turn.

Sacrifice a creature: Exile the top card of your library. Until end of turn, you may play that card.

Venerated Beast can't be blocked by more than one creature.

Flying
Whenever an opponent discards a card, put a +1/+1 counter on Nightbane Specter.
Whenever Nightbane Specter deals combat damage to a player, that player discards a card.

Death knell — Put a trample counter on target creature you control. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)
Sacrifice a creature: Put a +1/+1 counter on Crushing Victor. Activate only as a sorcery.

{G}, {T}: Put a +1/+1 counter on Bloodleaf Tracker for each creature that entered this turn.

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell with a creature type no creature you control has.

Trawler Skaab gets +1/+1 for each card put into your graveyard from your library this turn.

When Intrepid Shieldmate enters, target creature gets +1/+1 until end of turn.

When Herd Matron enters, distribute two +1/+1 counters among one or two target creatures you control.

Until end of turn, creatures you control get +1/+1 and creatures your opponents control get -1/-1.

Whenever Spirit of Infamy attacks, post a bounty on target creature. (Put a bounty counter on that creature. It has “When this creature dies, each opponent draws a card” as long as it has a bounty counter on it.)
Spirit of Infamy gets +2/+0 for each bounty counter on it.

Whenever a -1/-1 counter is put on a creature you control, you gain 1 life.
{1}{B}, Pay 1 life: Untap target Cleric. You may remove a -1/-1 counter from that creature.

This spell costs {3} less to cast if a creature died this turn.
Put target creature card with mana value X from a graveyard onto the battlefield under your control.

Erosive Path enters tapped unless you control one or fewer other lands.
{T}: Add {B} or {R}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Transcend (Activate as a sorcery to gain the next type and a +1/+1 counter.)
When Mahara enters, if you cast them, destroy all other creatures.
{W}{B}: Angel — You gain 4 life and amass Soldiers 4. (Put four +1/+1 counters on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)
{5}{W}{B}: Elder — Amass Soldiers 20.

Somber Meadow enters tapped.
{T}: Add {W} or {B}.
{1}, {T}: Add one mana of any color.

Primal—{W}, Exile a creature you control. (During your turn, you may cast this spell by paying {W} and exiling a creature you control instead of playing a land.)
When Planar Eviction enters, exile another target nonland permanent until Planar Eviction leaves the battlefield.

Haste
Whenever Spellmaw Crocodile deals combat damage to a player, draw a card.
Discard a card: Spellmaw Crocodile can't be blocked this turn.

When Prophet of Reclamation dies, mill three cards, then return up to one land card from your graveyard to your hand.

Raider's Den enters tapped.
{T}: Add {R}.
{R}, {T}: Target creature you control gains menace until end of turn. Activate only as a sorcery and only if you control a red creature.