=0 Card Game
A daily puzzle of mental math
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
One board a day, the same one for everyone:
seven cards, one number, and no hints of any kind.
Bring it to exactly zero before the equations run out.
Everything must equal zero.
= 0 is a roguelike built out of arithmetic. You are dealt seven operation cards and a core number, and you have to bring that number to exactly zero before you run out of equations. Land it precisely and the proof pays. Miss it and the auditors take the difference.
THE DAILY BOARD
One board a day, the same one for everyone. Same opponents, same cores, same hands, same shop stock in the same order. Play it as many times as you like, then share a scorecard that shows how far you got without giving away the route you took.
NO HINTS
Nothing lights up to tell you a division lands clean or a subtraction reaches zero. No suggested moves, no undo, no preview of what a card would do. The mental arithmetic is the game - the interface only deals the cards and keeps the score.
ONE RUN
Seven stops: five fights and two shops, ending at INFINITY. Every opponent rewrites a rule while you fight it. THE MIRROR reverses addition and subtraction. THE DIVIDER is immune unless you divided this equation. THE AUDITOR rejects any proof of fewer than four cards, and THE MINIMALIST halves any proof of more than three. THE CLERK taxes every third operation you play. INFINITY takes the ceiling off momentum, and off itself.
BUILD SOMETHING
Fifteen proofs pay out for the shape of a solution, not just the answer - a single stroke, a perfect square, a prime landing, a climb, a freefall, a close call.
Axioms change the rules of arithmetic for the rest of a run. Exact zero doubles your momentum. Every division you play compounds it. The core is allowed below zero, and coming back from red pays double.
Lemmas are one-use outs for a hand that will not solve.
And the press stamps editions onto a card you choose: one that lands twice, one that leaves a carbon copy behind, one that ages a point every fight you survive.
FREE AND PAID
The daily board is free, with unlimited replays. A single In-App Purchase, bought once, unlocks unlimited seeds - roll a new run whenever you want, or type in a friend's three-word code and play their exact board.
No account. No ads. No timers. Plays offline.
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The developer, Mai Studio OU, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
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- Purchases
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Information
- Seller
- Mai Studio OU
- Size
- 48 MB
- Category
- Card
- Compatibility
Requires iOS 16.4 or later.
- iPhone
Requires iOS 16.4 or later. - iPad
Requires iPadOS 16.4 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- =0 Unsupervised $1.99
- Copyright
- © MAI STUDIO OU