msem-instigator

Other Rebel creatures you control get +1/+0.
When Youthful Renegade enters, create a 1/1 white Rebel creature token.

{2}{B}, Sacrifice a Clue: Target creature gets -3/-3 until end of turn.

Flying
Whenever you attack with three or more creatures, exile the top card of your library. You may play that card until you exile another card with Zarthane, Scourge of Galdurheim.
{2}{B/R}: Target creature gets +1/+0 and gains menace until end of turn. Activate only as a sorcery.

{1}, {T}, Move a -1/-1 counter from another creature onto Zealous Bloodletter: Proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Voracious 1 (As this enters, you may sacrifice an artifact or creature. If you do, it enters with a +1/+1 counter on it.)
At the beginning of combat on your turn, if you sacrificed a permanent this turn, target creature you control gains trample and haste until end of turn.

Trample
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Whenever two or more creatures an opponent controls block, adjudicate. (Create a white Aura enchantment token with enchant creature and “Sacrifice this token: Untap enchanted creature” attached to target creature.)
Enchanted creatures you control have menace.

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

Whenever Zealous Scaleblight becomes tapped, it deals 1 damage to any target.

Flash
When Zhedina Coastguard enters, you may have any number of creatures you control have base power and toughness 1/3, 2/2, or 3/1 until end of turn.

When Zhedina Envoys leaves the battlefield, create two 1/1 Scout creature tokens that are all colors.

Lifelink
When Zhehan, the Mediator enters, you may put an Aura card with mana value 3 or less from your hand onto the battlefield attached to a creature it could enchant.

(Transcend as a sorcery to gain that type and a +1/+1 counter.)
Menace
{2}{B}: Demigod — Surveil 2. Each opponent loses 2 life and you gain 2 life.
{4}{B}: God
Search your library for two cards with different names and reveal them. An opponent chooses one. Put the chosen card into your graveyard and the rest into your hand. Then shuffle.

When Zoetic Tomb enters, exile target creature.
{4}: Until end of turn, Zoetic Tomb becomes a Golem artifact creature with power and toughness equal to the exiled creature's base power and toughness.

Enchantment spells you cast cost {1} less to cast.
Enchantment creatures and enchanted creatures you control get +1/+1.

As an additional cost to cast this spell, sacrifice an artifact.
Draw three cards.

Target creature gets -2/-0 until end of turn. If that creature is tapped, draw a card.

Whenever an enchantment you control enters or Zoulev Ritualist becomes enspirited, draw a card.

Menace
When Zygos's Decimators enters, put a number of +1/+1 counters on it equal to your devotion to black. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

When 1-ST Thankless Companion enters, draw a card.

Equipped creature has vigilance. (Attacking doesn't cause that creature to tap.)
Equip {1}

Reprise {3}{B} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)
This spell deals 2 damage to target creature. You gain life equal to the total damage dealt by this spell.

When AOSE Extractor enters, crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)

Vigilance
Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)

When AOSE Lab Tech enters, draw three cards, then discard two cards unless you discard an artifact card.