Slick Sequence

Slick Sequence deals 2 damage to any target. If you've cast another spell this turn, draw a card.

Shackle Slinger

Whenever you cast your second spell each turn, choose target creature an opponent controls. If it's tapped, put a stun counter on it. Otherwise, tap it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Slickshot Vault-Buster

Vigilance
This creature gets +2/+0 as long as you've committed a crime this turn. (Targeting opponents, anything they control, and/or cards in their graveyards is a crime.)

Trick Shot

Trick Shot deals 6 damage to target creature and 2 damage to up to one other target creature token.

Razzle-Dazzler

Whenever you cast your second spell each turn, put a +1/+1 counter on this creature. It can't be blocked this turn.

Malcolm, the Eyes

Flying, haste
Whenever you cast your second spell each turn, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Thunder Salvo

Thunder Salvo deals X damage to target creature, where X is 2 plus the number of other spells you've cast this turn.

Stella Lee, Wild Card

Whenever you cast your second spell each turn, exile the top card of your library. Until the end of your next turn, you may play that card.
{T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy. Activate only if you've cast three or more spells this turn.

Quick Draw

Target creature you control gets +1/+1 and gains first strike until end of turn. Creatures target opponent controls lose first strike and double strike until end of turn.

Deadeye Duelist

Reach
{1}, {T}: This creature deals 1 damage to target opponent.

Captain Ripley Vance

Whenever you cast your third spell each turn, put a +1/+1 counter on Captain Ripley Vance, then it deals damage equal to its power to any target.

Breeches, the Blastmaker

Menace
Whenever you cast your second spell each turn, you may sacrifice an artifact. If you do, flip a coin. When you win the flip, copy that spell. You may choose new targets for the copy. When you lose the flip, Breeches deals damage equal to that spell's mana value to any target.

Kraum, Violent Cacophony

Flying
Whenever you cast your second spell each turn, put a +1/+1 counter on Kraum and draw a card.

Outlaw Stitcher

When this creature enters, create a 2/2 blue and black Zombie Rogue creature token, then put two +1/+1 counters on that token for each spell you've cast this turn other than the first.
Plot {4}{U} (You may pay {4}{U} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Rodeo Pyromancers

Whenever you cast your first spell each turn, add {R}{R}.

Jori En, Ruin Diver

Whenever you cast your second spell each turn, draw a card.

Iron-Fist Pulverizer

Reach
Whenever you cast your second spell each turn, this creature deals 2 damage to target opponent. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Brimstone Roundup

Whenever you cast your second spell each turn, create a 1/1 red Mercenary creature token with "{T}: Target creature you control gets +1/+0 until end of turn. Activate only as a sorcery."
Plot {2}{R} (You may pay {2}{R} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Incursion Specialist

Whenever you cast your second spell each turn, this creature gets +2/+0 until end of turn and can't be blocked this turn.

Loan Shark

When this creature enters, if you've cast two or more spells this turn, draw a card.
Plot {3}{U} (You may pay {3}{U} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)