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Project Sekai

131701
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8–12 Zaps / turn

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Frequently asked questions

What is Project Sekai?

Project Sekai is an AI simulation world on WorldOS: you make the calls and the AI plays out the story, characters, and consequences in real time. Every run is different.

How do I play Project Sekai online?

You play Project Sekai online right in your browser — nothing to download. Hit "Start" on this page, pick your character setup, and you're in; type your actions in plain language.

Is Project Sekai free to play online?

Yes. Your first visit after each 24-hour window automatically starts a free Zap allowance (no card needed) — enough to play Project Sekai regularly. Want more? There are subscription plans.

Is there a Project Sekai app?

WorldOS runs in your mobile and desktop browser, so you can play Project Sekai online without installing anything.

What are some games like Project Sekai?

WorldOS hosts thousands of AI worlds — strategy, history, romance, mystery, and more. Browse the gallery to find more games like Project Sekai.

Can I make my own Project Sekai?

Yes. Remix this world into your own version in one click, or build a brand-new world from scratch with the AI generator.

Browse all worlds →