Terms of Use and Privacy
Last updated 28 September 2026
Terms of Use
Nucleo is a free idle game about collecting the chemical elements, run by the developer of Nucleo, S. Rucadr (“we”, “us”). By playing Nucleo you agree to these terms. If you don’t agree, please don’t play.
1. The game
- Nucleo is free to play. There are no in-game purchases, and nothing in the game costs real money.
- We may change, balance, add or remove features, content, bonuses and rewards at any time, and we may pause or end the game. Progress, multipliers and in-game items have no monetary value and can’t be exchanged for money.
- The game is provided “as is”. We do our best to keep it running and your progress safe, but we can’t promise it will always be available, bug-free or that progress will never be lost.
2. Fair play
- Don’t cheat: no editing saves or requests to fake progress, no automated scripts against our servers, no creating accounts to get around limits, and no exploiting bugs on purpose. Please report bugs instead.
- Don’t attack, overload or try to break into the game or its servers.
- We may remove or reset leaderboard entries, community-project contributions and rewards that we believe were gained unfairly, and block access where needed.
3. Display names
- Your display name is public on the leaderboard and in community projects. Choose a name that isn’t offensive, hateful, sexual or impersonating someone else, and that contains no personal information you don’t want public.
- We filter names automatically and may change or remove any name we consider inappropriate.
4. Enjin Wallet and NFTs
- Signing in with an Enjin Wallet is optional. It only proves you own the wallet: nothing is signed or spent. The Enjin Wallet and the Enjin Platform are run by Enjin under their own terms and privacy policy, and you need to meet their requirements (including age) to use them.
- Nucleo NFTs give in-game bonuses while they are held in the wallet you signed in with. Those bonuses are a game feature, not a promise: we may rebalance or change them. We don’t sell NFTs in the game, and nothing in Nucleo is an investment, financial product or offer of value. Any trading of NFTs happens outside the game, at your own risk.
- Blockchain transfers are final. We can’t reverse transfers, recover lost wallets or replace NFTs sent to the wrong address.
- Your progress is linked to your wallet while you are signed in. Unlinking deletes the wallet’s cloud save; signing out keeps it with the wallet.
5. Community projects and rewards
- Community projects, their rewards and any NFT drops are given at our discretion. We decide eligibility, may change or cancel a reward, and may exclude contributions we believe were not fair. Being eligible does not create a right to a reward.
- NFT rewards can only be sent to contributors who were signed in with an Enjin Wallet.
6. Liability
To the fullest extent the law allows, we are not liable for indirect or consequential losses, lost progress, or losses related to NFTs, wallets or third-party services. Nothing in these terms limits rights you have under mandatory consumer law where you live.
7. Changes
We may update these terms. The date at the top shows the latest version, and important changes will be announced in the game’s What’s new list. Continuing to play means you accept the updated terms.
8. Educational content
The facts in the game’s Catalog are written to be accurate and are simplified for play. They’re for learning and fun, not a scientific reference.
Privacy Policy
Nucleo collects as little as possible. There are no ads, no analytics or tracking, and no cookies. You don’t need an email address or real name to play.
What is stored on your device
Your game progress is saved in your browser’s local storage. It includes a random player id and a secret key that the game creates, so your leaderboard entry can only be updated by you. Nothing here leaves your device unless you use the online features below.
What is stored on our servers
| Feature | What we store | Why |
|---|---|---|
| Leaderboard (automatic while you play online) | Your random player id, a one-way hash of your secret key (not the key itself), your display name, elements collected, objects cataloged, lifetime energy and supernova/kilonova counts, and when your entry was created and updated. For the weekly leaderboard, your elements and level at the start of each week, kept for five weeks. | To show the global leaderboard. |
| Enjin Wallet sign-in (optional) | Your public wallet address, which Nucleo NFTs it holds and when they were last checked, your cloud save (your game progress, including your player id and secret key, so it works on your other devices) and a short-lived sign-in code. To limit abuse, a salted one-way hash of your connection’s IP address with an hourly count of sign-in codes, kept for at most two days. | To let your progress follow your wallet and to give NFT bonuses. |
| Backup code (optional, guests) | Your player id, a one-way hash of your secret key, your game progress (updated every few minutes while you play) and a one-way hash of your backup code (not the code itself). To limit guessing, a salted one-way hash of your connection’s IP address with a daily count of restore attempts, kept for at most two days. | To let you continue your game on another device. |
| NFT drops | When you open Profile, the game sends your player id, secret key and the ids of your achievements so the server can check which drops you qualify for. Nothing from this check is stored, except when you reveal a single-use code: then which code went to your player id is kept, so it stays yours and is never given to anyone else (erasing your data removes the link to you), and a salted one-way hash of your connection’s IP address with a daily count, kept for at most two days, limits how many codes one connection can take. | To show you the NFT drops you’ve earned. |
| Community projects (when open) | Your player id, display name, how many shipments you sent and when, and, to limit abuse, a salted one-way hash of your connection’s IP address with a daily count, kept for at most two days. | To run shared projects and give contributor rewards. |
For community-project NFT rewards, we look up the wallet addresses of contributors who were signed in with an Enjin Wallet, to send the NFTs.
Services we use
- Vercel hosts the game and runs its server functions. Like any web host, it processes your IP address and technical request data to deliver the game, and may keep short-term logs.
- Neon hosts the database that stores the data in the table above.
- Enjin handles wallet sign-in and tells us which Nucleo NFTs a wallet holds, when you use those features.
- Google Fonts serves the game’s typeface, so your browser contacts Google when loading the game.
These providers may process data outside your country, including outside the EU/EEA, under their own safeguards. We don’t sell your data or share it with anyone else.
Public information
Your display name, rank and game stats are visible to everyone on the leaderboard, and your name may appear among a project’s top builders. Holding Nucleo NFTs shows a ◆ next to your name. Your wallet address is not shown in the game, although wallet contents are public on the blockchain by nature.
How long we keep it and how to delete it
- We keep your online data while you play, and delete it when you ask.
- Profile → Erase all progress deletes your game on the device and your online data: your leaderboard entry, wallet link and cloud save, backup, and project shipments. Contributions to finished projects may be kept if they were already used to send rewards.
- Delete backup (Profile → Backup code) deletes your online backup; its code stops working.
- Unlink wallet deletes your wallet link and cloud save but keeps playing on your device.
- If you can’t use the game to delete your data, contact us (below) with your display name and we’ll help.
Keep your code private
Anyone who has your backup code can copy your progress to their device and play as you. Keep it to yourself; if it leaks, make a new code (the old one stops working) or delete the backup.
Your rights
Depending on where you live (for example under the GDPR in the EU/EEA), you have the right to access, correct, delete or get a copy of your data, to object to or restrict how it’s used, and to complain to your data protection authority. We use your data to provide the game you asked for (contract) and, for anti-abuse limits, our legitimate interest in fair play.
Children
Nucleo is suitable for all ages and collects no names, emails or contact details. Online features show only a chosen display name; children should avoid using their real name. Enjin Wallet features are subject to Enjin’s age requirements.
Contact
Questions, data requests or reports: message S. Rucadr on X at @rucadr.
These pages describe how Nucleo works today and are written in plain language. They are not a substitute for legal advice.