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.

Gut Shot

({R/P} can be paid with either {R} or 2 life.)
Gut Shot deals 1 damage to any target.

Fury of the Horde

You may exile two red cards from your hand rather than pay this spell's mana cost.
Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

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.")

Mishra's Bauble

{T}, Sacrifice this artifact: Look at the top card of target player's library. Draw a card at the beginning of the next turn's upkeep.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Sakura-Tribe Elder

Sacrifice this creature: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Jori En, Ruin Diver

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

Manamorphose

Add two mana in any combination of colors.
Draw a card.

Cori-Steel Cutter

Equipped creature gets +1/+1 and has trample and haste.
Flurry — Whenever you cast your second spell each turn, create a 1/1 white Monk creature token with prowess. You may attach this Equipment to it. (Whenever you cast a noncreature spell, the token gets +1/+1 until end of turn.)
Equip {1}{R}

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Urza's Bauble

{T}, Sacrifice this artifact: Look at a card at random in target player's hand. You draw a card at the beginning of the next turn's upkeep.

Eshki Dragonclaw

Vigilance, trample, ward {1}
At the beginning of combat on your turn, if you've cast both a creature spell and a noncreature spell this turn, draw a card and put two +1/+1 counters on Eshki Dragonclaw.

Flare of Cultivation

You may sacrifice a nontoken green creature rather than pay this spell's mana cost.
Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Mutagenic Growth

({G/P} can be paid with either {G} or 2 life.)
Target creature gets +2/+2 until end of turn.

Temur Battlecrier

During your turn, spells you cast cost {1} less to cast for each creature you control with power 4 or greater.

Noxious Revival

({G/P} can be paid with either {G} or 2 life.)
Put target card from a graveyard on top of its owner's library.

Ledger Shredder

Flying
Whenever a player casts their second spell each turn, this creature connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)