msem-instigator

Soul of Misery gets +1/+1 as long as you control a Swamp.
{4}{B}: Target player discards a card. Activate only as a sorcery.

{1}, {T}, Sacrifice Soul-Synthesizer: Look at the top seven cards of your library. You may reveal a card with an activated ability from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Other Spirits you control get +1/+1.
As long as a Spirit you control has flying, Soulcleaver has flying. The same is true for first strike, double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, reach, trample, and vigilance.

At the beginning of each end step, if you gained life this turn, put a +1/+1 counter on a creature you control.

Flash
Other Rogues you control get +1/+1.
Rogue spells you cast have flash.

Destroy target creature. Then if you control a Wizard, that creature's controller loses 1 life for each creature card in their graveyard.

Flying
Whenever Souls of the Jury enters or an opponent fails a trial, create a 1/1 white Cleric creature token.

{3}, {T}, Sacrifice a non-Spirit creature: Create a 1/1 white Spirit creature token with flying.

If target creature would leave the battlefield this turn, return it to its owner's hand instead.
Fuse (You may cast one or both halves of this card from your hand.)

Source Decay deals 2 damage to each opponent. Create two 1/1 colorless Servo artifact creature tokens.
Whenever a creature you control deals combat damage to a player, you may pay {2}{B}{R} and sacrifice it. If you do, return Source Decay from your graveyard to your hand.

Trample
Whenever a creature dealt damage by Sovereign of Old Lovi this turn dies, put a +1/+1 counter on Sovereign of Old Lovi.

All creatures get -2/-2 until end of turn. At the beginning of the next end step, if three or more creatures died this turn, create two tapped Treasure tokens.

Flash
Flying
Whenever you cast a spell during an opponent's turn, target permanent doesn't untap during its controller's next untap step.

Whenever a land you control enters, you gain 1 life.
{3}{G}, Sacrifice Sower of Spring: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Whenever Sower of Virulent Thoughts attacks, you may return a creature you control to its owner's hand. If you do, put a +1/+1 counter on target creature you control.

Exile target creature. That creature's controller reveals cards from the top of their library until they reveal a creature card. That player puts that card onto the battlefield, then shuffles the rest into their library.

Menace
When Spaceship Invader enters, destroy target creature you don't control with mana value 3 or less.

Destroy each creature with power 3 or greater.

Exile the top card of your library. You may have Spark Inspiration deal 2 damage to each opponent. If you don't, you may play that card until end of turn.

Spark New Life deals X damage to any target. You may put up to X land cards from your hand and/or graveyard onto the battlefield.

Primal {2}{R} (During your turn, you may cast this spell for {2}{R} instead of playing a land.)
Target creature gets +2/+0 and gains double strike until end of turn.

Sparring Ground enters with a +1/+1 counter on it.
{T}: Add {C}.
Whenever a creature you control enters, you may move a +1/+1 counter from Sparring Ground onto that creature.

Flying, haste
Whenever Spawn of Hadak attacks, draw a card, then discard a card.

Trample
When Spawn of Qiyan enters, distribute four +1/+1 counters among any number of target creatures you control.
{2}{G}: Put Spawn of Qiyan from your graveyard into your library second from the top.

Menace
Whenever you cast a cryptic spell, you may return target creature card from your graveyard to your hand. (Artifacts, enchantments and modal spells are cryptic.)