msem-instigator

If another creature you control would die, exile it instead.
When John Furo, the Unfortunate dies, until your next end step, you may play cards exiled with John Furo.

First strike
Spells can't be cast except during their controller's turns.
Whenever a creature attacks you, Ka Soma deals 1 damage to that creature's controller unless that player pays {1}.

Whenever a creature attacks Kalro, Desert Outpost, it deals 1 damage to that creature.
[+1]: Create a 1/1 red and white Sand Warrior creature token.
[–2]: Destroy target nonbasic land. Its controller creates a colorless Desert land token with “{T}: Add {C}.”

Rhapsody {5}{R}{W} (Pay {5}{R}{W} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
Whenever a creature you control with power 4 or greater attacks, look at the top four cards of your library. You may cast a nonland card with mana value 3 or less from among them without paying its mana cost. Put the rest on the bottom of your library in a random order.

Whenever Lackeybot deals damage to a player, choose an artifact card with mana value X or less at random, where X is the amount of damage dealt. You may create a token that's a copy of that card.

Other Actors you control get +1/+1.
Whenever a permanent you control transforms, Lantern Tender deals 2 damage to any target and you gain 2 life.

Creatures you control get +X/+0 and gain first strike until end of turn.

Whenever a non-Spirit creature you control dies, you may create a token that's a copy of that creature except the token is a Spirit in addition to its other types and has haste.

Enchant creature
Enchanted creature has “Whenever this creature attacks, attacking creatures you control get +1/+1 until end of turn.”

As an additional cost to cast this spell, tap X untapped creatures you control.
Lightning Chorus deals X damage to any target and you gain X life.

Trample, haste
Whenever Lisseria, General of Kanaa attacks, you may exchange its power with the power of target creature defending player controls until end of turn.

Livia's name is Senaturian Legion in addition to its other names as long as it's on the battlefield.
At the beginning of your upkeep, conjure a card named Senaturian Legion into your hand, then discard a card. (It's a 1/1 Human Soldier for {W}{W} that gets +1/+1 for each other creature on the battlefield named Senaturian Legion.)
Other Soldiers you control have haste.

At the beginning of each opponent's upkeep, choose one —
• At the beginning of the next end step, if you haven't been dealt combat damage this turn, Lord Dalehorn the Iron-Handed deals 3 damage to that player.
• At the beginning of the next end step, if that player hasn't cast a creature spell this turn, Lord Dalehorn the Iron-Handed deals 3 damage to that player.

First strike, haste
Whenever Lothaire attacks, create a 0/0 colorless Reflection creature token that's tapped and attacking. Creatures you control get +1/+1 until end of turn.
{2}{R}{W}: Put a +1/+1 counter on each creature you control.

Whenever you make first contact, create a 1/1 white Bird creature token with flying. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)
Whenever three or more creatures you control deal combat damage to a player, create a token that's a copy of another target permanent you control.

You may put a creature or planeswalker card from your hand onto the battlefield. If it's a creature, it gains haste and indestructible. Return it to your hand at the beginning of your next end step.

Creatures you control attacking cause abilities of that creature to trigger as though it entered.
Once each turn, when you attack, you may pay {1}{R/W}. When you do, untap target attacking creature. After this phase, there is an additional combat phase.

When you cast this spell, copy it for each Reflection creature you control. You may choose new targets for the copies.
Mirrorstorm deals 1 damage to any target and you gain 1 life.

Cast this spell only during the declare blockers step.
After this step there's an additional declare attackers step followed by an additional declare blockers step. (A creature can't attack or block again if it's already attacking or blocking.)
Draw a card.

Target creature gets +1/+1 until end of turn.
Fabled {2}{R/W}{R/W} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that creature.)

When Monk of Mid-Autumn enters, choose one —
• Put a double strike counter on Monk of Mid-Autumn.
• Destroy target artifact or enchantment.
• Monk of Mid-Autumn deals 2 damage to target tapped creature and you gain 2 life.

Trial 2 (As you cast this spell, an opponent of your choice may pay 2 life. If they don't, they fail the trial.)
When Nascent Adversary enters, if the trial was failed, it gains haste and first strike until end of turn.

Prowess
When One of Purpose enters, if you cast it, create a Function token with “If you cast this spell from your hand, exile it. You may cast it from exile until the end of your next turn.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Lifelink
Whenever Painstriker attacks, it deals 2 damage to target creature defending player controls.

Other creatures you control get +1/+0.
{R}{W}: Create a 1/1 red and white Warrior creature token. That token gains haste. Exile it at the beginning of the next end step. Activate only as a sorcery.