Verazol, the Split Current

Verazol, the Split Current enters the battlefield with a +1/+1 counter on it for each mana spent to cast it.
Whenever you cast a kicked spell, you may remove two +1/+1 counters from Verazol. If you do, copy that spell. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Into the Roil

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
Return target nonland permanent to its owner's hand. If this spell was kicked, draw a card.

Inscription of Insight

Kicker {2}{U}{U}
Choose one. If this spell was kicked, choose any number instead.
• Return up to two target creatures to their owners' hands.
• Scry 2, then draw two cards.
• Target player creates an X/X blue Illusion creature token, where X is the number of cards in their hand.

Vineshaper Prodigy

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
When Vineshaper Prodigy enters the battlefield, if it was kicked, look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Roost of Drakes

Kicker {2}{U} (You may pay an additional {2}{U} as you cast this spell.)
When Roost of Drakes enters the battlefield, if it was kicked, create a 2/2 blue Drake creature token with flying.
Whenever you cast a kicked spell, create a 2/2 blue Drake creature token with flying.

Murasa Sproutling

Kicker {1}{G} (You may pay an additional {1}{G} as you cast this spell.)
When Murasa Sproutling enters the battlefield, if it was kicked, return target card with a kicker ability from your graveyard to your hand.

Elvish Hydromancer

Kicker {3}{U} (You may pay an additional {3}{U} as you cast this spell.)
When Elvish Hydromancer enters the battlefield, if it was kicked, create a token that's a copy of target creature you control.

Inscription of Abundance

Kicker {2}{G}
Choose one. If this spell was kicked, choose any number instead.
• Put two +1/+1 counters on target creature.
• Target player gains X life, where X is the greatest power among creatures they control.
• Target creature you control fights target creature you don't control.

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Joint Exploration

Kicker {G} (You may pay an additional {G} as you cast this spell.)
Scry 2, then draw a card. If this spell was kicked, you may put a land card from your hand onto the battlefield.