msem-instigator

Kernel Barrage deals damage to target creature or planeswalker equal to the number of spells you've cast this turn (including this one).
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Enchant opponent
Creatures attacking enchanted player get +2/+0.
{R}, Discard Kernel Flare: Draw a card.

At the beginning of combat on your turn, you may have Kym, New Hope become a 4/2 Warrior creature with first strike and haste until end of turn. (They don't lose loyalty while not a planeswalker.)
[+1]: Create a red enchantment token named Blitz with “Whenever you attack, target attacking creature gets +1/+0 until end of turn.”
[–2]: Whenever you attack with one or more creatures this turn, Kym, New Hope deals that much damage to any target.

Loaded Gift deals 3 damage to any target. If any opponent is cursed, Loaded Gift deals 4 damage to that permanent or player instead.

When you cast this spell from anywhere other than your hand, it deals 5 damage to any target.
Trample

When Mirror Paradigm enters, conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)
Once each turn, when a sorcery card is put into your graveyard from anywhere, you may copy it. If you do, you may cast the copy. (You still pay its costs.)

Neon Claw Assassin gets +1/+0 and has first strike as long as you've discarded a card this turn.

Whenever Neon Claw Knight enters or attacks, choose one. Create a Function token with that effect. (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)
• This spell can't be countered.
• This spell costs {R} less to cast.
• If this spell would deal damage to a permanent or player, it deals that much damage plus 1 instead.

As an additional cost to cast this spell, you may discard two cards. If you do, this spell costs {3} less to cast and it can't be countered.
Exile the top three cards of your library. You may play those cards until the end of your next turn.

Null Bit deals 3 damage to any target.
You may discard a card. If you do, draw a card.

You may cast cast up to two target instant and/or sorcery cards with total mana value 6 or less from your graveyard without paying their mana costs. If a spell cast this way would be put into your graveyard, exile it instead.
Exile Pointer Churn.

Whenever you cast an instant or sorcery spell, you may conjure two duplicates of it into your main library, then shuffle. Then if there are two or more cards in your graveyard that share a name with that spell, copy it. You may choose new targets for the copy.

Exile twice X cards from the top of your library. During your next turn, you may play cards exiled this way.

Enchant opponent
Whenever enchanted player is attacked, choose an attacking creature. Create a tapped and attacking token that's a copy of it. Exile the token at the beginning of the next end step.

Reach
Whenever you cast a spell with mana value 5 or greater, Reaper Squad deals 3 damage to target player or planeswalker.

Target instant or sorcery card in your graveyard gains flashback until end of turn. Its flashback cost is equal to its mana cost.
Flashback—{R}, Discard a card. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Instant, sorcery, and enchantment spells you cast cost {1} less to cast.

Prowess
When Rosebud Runner enters, exile the top card of your library. During your next turn, you may play that card from exile.

Discard a card, draw a card, then conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
At the beginning of your end step, discard a card. Then draw a card if an opponent is cursed.

Whenever you cast a spell with mana value greater than Script Jockey's power, put a +1/+1 counter on Script Jockey.

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
Each cursed opponent must attack with at least one creature each combat if able.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you casting a noncreature spell causes an ability of a creature you control to trigger, that creature gains your choice of first strike, haste, menace, or trample until end of turn.

As long as it's your turn, Shell Merc has first strike and prowess.

Whenever you discard an instant or sorcery card, you may cast it from your graveyard. (You still pay its costs.)
Spells you cast from anywhere other than your hand cost {1} less to cast.