Support
Frequently asked questions.
Answers to the questions we hear most from new and returning players, covering the simulator itself and general Union Arena play. Still stuck? Reach out through our Contact page.
Getting Started
Is Cardboard Kitsune free to play?
Yes. Deck building, matchmaking, and full games are free. Some optional cosmetic and community features exist, but core gameplay is never locked behind a purchase.
Do I need to download anything?
No. Cardboard Kitsune runs entirely in your browser - build decks, challenge friends, and play full matches without installing an app or client.
Do I need an account to play?
You can browse most of the site without one, but you will need a free account to save decks, join ranked matches, and track your match history.
Is this an official Union Arena product?
No. Cardboard Kitsune is an independent, unofficial fan-made simulator and is not affiliated with, endorsed by, or sponsored by Bandai, Bandai Namco, or Shueisha. See our About page for the full disclosure.
Decks & Cards
How do I build a deck?
Open the Deck Builder from the main menu, search or filter for cards, and add them to your deck list. The tool enforces the standard 50-card main deck and copy limits as you build.
Where does the card data come from?
Card data and images are generously provided by Exburst. You can find a link to them in the footer of every page.
Can I import an existing decklist?
Yes, the deck builder supports importing decklists so you do not have to add every card by hand.
New to deck building entirely?
Start with our Deck Building Guide, which walks through core stats, archetypes, and a testing checklist for putting a deck together from scratch.
Playing Matches
How do I start a match?
Head to the Lobby to find an open match or create your own, or challenge a friend directly from your friends list.
Can I play against a friend directly?
Yes. Add them as a friend from your account, then send a direct challenge instead of queuing through the open lobby.
Is there ranked play?
Yes - check the Leaderboards page to see current standings and how ranked matches factor into it.
What do I do if I run into a bug during a match?
Please report it through the Contact page with as much detail as you can - what happened, what you expected, and which cards or actions were involved. That detail is what actually gets bugs fixed quickly.
Account & Support
How can I support the project?
Cardboard Kitsune is a fan-run passion project with real hosting and development costs. Visit the Support page to see the available ways to chip in.
I forgot my password. What do I do?
Use the "Forgot Password" link on the login panel to request a reset email.
How do I report another player?
You can block a player directly from your account, and you are welcome to reach out through the Contact page for anything that needs a closer look.
Where can I read about privacy and data handling?
See our Privacy Policy, Terms of Service, and Legal Disclaimer, all linked in the site footer.
Still have a question?
We're happy to help with anything not covered here - account issues, bug reports, or general feedback.
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Kitsune
The world's first simulator for the Union Arena trading card game.
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