msem-instigator

Menace
Whenever you cast a glitched spell, Null Entity gets +2/+0 until end of turn for each time that spell was glitched.

Oathbreaker Orc attacks each combat if able.
Whenever Oathbreaker Orc attacks, it deals 2 damage to defending player unless that player sacrifices a permanent.

Whenever Orphan Prodigy is dealt damage, it deals that much damage to target player.
Attain {4}{R} ({4}{R}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Your opponents can't gain life.
If a source you control would deal damage to an opponent, it deals that much damage plus 1 instead.
{3}{R}: Transform Pyromantic Duo. Activate only if it's attacking.

Trample
When Rallios's Champion enters, look at the top six cards of your library. You may put a Warrior card with lesser mana value from among them onto the battlefield. Put the rest on the bottom of your library in a random order.
Other Warriors you control get +1/+1.

Rhapsody {4}{R}{R} (Pay {4}{R}{R} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
When Reckless Guardian dies, create X 1/1 colorless Servo artifact creature tokens, where X is Reckless Guardian's power.

Bleed {2}{R}{R} (You may cast this spell for its bleed cost if an opponent has lost life this turn.)
When Restless Hedonist enters, discard your hand, then draw three cards.

Each instant and sorcery card in your hand has orchestrate. Its orchestrate cost is equal to its mana cost reduced by {2}. (You may exile those cards from your hand anytime you could cast a sorcery for their orchestrate cost. When you next resolve a spell, you may cast it from exile without paying its mana cost.)
When you cast your third spell this turn, exile Reytali, then return her to the battlefield transformed.

Whenever Roving Dreadnought attacks, you may salvage a card that was put into your graveyard this turn. (Exile one from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)

Whenever you cast a noncreature spell, Sara, Entelan Elementalist gets +X/+0 until end of turn, where X is Sara's power. It deals 1 damage to each creature you don't control.

Flying
Whenever you cast an instant or sorcery spell, Scourge of the Sun gets +1/+0 until end of turn. If you spent four or more mana to cast that spell, Scourge of the Sun gets an additional +1/+0 until end of turn.

When Smuggler of the Santriza enters, you may discard a card. If you do, draw a card.

Whenever you cast a noncreature spell, this creature gets +1/+0 and gains first strike until end of turn. Surveil 1.

Sparkmage Prodigy has first strike as long as it's your turn.
Whenever you cast a cryptic spell, Sparkmage Prodigy deals 1 damage to each opponent. (Artifacts, enchantments, and modal spells are cryptic.)

Prowess
Disgraced 2 (This enters with two -1/-1 counters. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)

Haste
{T}, Discard a card: Flip a coin. If you win the flip, draw two cards. Otherwise, you may pay {R}. If you do, repeat this process.

Double strike
At the beginning of each end step, if a creature you control died this turn, Tempered Survivor deals 2 damage to each opponent.

Whenever Thunderwolf attacks, exile the top card of your library. You may play that card this turn.

Whenever Trusted Comrade and at least one other creature attack, create a 1/1 white Soldier creature token that's tapped and attacking.

Vithian Arcanist gets +2/+0 and has haste as long as you've cast an instant or sorcery spell this turn.
When Vithian Arcanist enters, add {U}{B}{R}. Spend this mana only to cast instant and/or sorcery spells.

{2}{R}: Creatures you control get +1/+0 until end of turn.
{1}{G}: Creatures you control gain trample until end of turn.

When Yamisaran Guard enters, create a colorless Equipment artifact token with “Equipped creature gets +1/+1” and equip {1}.

When Adept of Rations enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Tokens you control have “{2}, {T}, Sacrifice this token: You gain 3 life.”

Whenever Agent of Vitu-Ghazi deals combat damage to a player, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Whenever a creature token you control enters, put a +1/+1 counter on target creature you control.