Blue white instant stealing

[indigo meadow]

Hey hey, I'm building a [[zethi]] deck based on using cost reducers to pump up x cost instant spells. While I was looking for cards I was looking at other colours and thinking, man there are some cool x cost instants. So I want to play them too but I can't find a blue white card that allows you actually cast someone elses spells. The closest I've found is [[wizard's spellbook]] but that doesn't fix your mana and needs a dice roll and has a high cmc.

So does anyone know of a blue white that allows you to cast your opponents instants?

[ebon leaf]

https://scryfall.com/card/slx/17/zethi-arcane-blademaster

Zethi, Arcane Blademaster <:mana1:292901508373282827><:manaw:1007102126813610074><:manau:292901508754702338>

Legendary Creature — Human Soldier
Multikicker
When Zethi, Arcane Blademaster enters the battlefield, exile up to X target instant cards from your graveyard, where X is the number of times Zethi was kicked. Put a kick counter on each of them.
Whenever Zethi attacks, copy each exiled card you own with a kick counter on it. You may cast the copies.
3/3

https://scryfall.com/card/afr/82/wizards-spellbook

Wizard's Spellbook <:mana5:292901508796645386><:manau:292901508754702338><:manau:292901508754702338>

Artifact
: Exile target instant or sorcery card from a graveyard. Roll a d20. Activate only as a sorcery.
1—9 | Copy that card. You may cast the copy.
10—19 | Copy that card. You may cast the copy by paying rather than paying its mana cost.
20 | Copy each card exiled with Wizard's Spellbook. You may cast any number of the copies without paying their mana costs.

[quartz phoenix]

Suggest posting a link to a deckbuilding website instead of a list. Automod sees it as spam

[indigo meadow]

Does txt work ?

[quartz phoenix]

that works; just harder for others to help when it's not on a deck website