> For the complete documentation index, see [llms.txt](https://suishadow.gitbook.io/suishadow/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://suishadow.gitbook.io/suishadow/welcome-to-suishadow.md).

# Welcome to SuiShadow

<figure><img src="/files/lSx77709puZZgFAphZO8" alt=""><figcaption><p>Shadow</p></figcaption></figure>

Welcome to **Sui Shadow**, a cutting-edge NFT marketplace on Sui where artists can sell truly “hidden” artworks—safe from theft or unauthorized re-minting. Instead of ever exposing a high-resolution PNG on-chain, Sui Shadow splits, encrypts, and stores image tiles off-chain, committing only a small Merkle root to the blockchain. Collectors who purchase an NFT gain permissioned, client-side access to decrypt and reassemble the full artwork in their browser.

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### The Challenge

Traditional NFT platforms mint clear-text images or store full media on decentralized storage, leaving them vulnerable to scraping, copying, or premature minting. Once exposed, an image can be stolen, re-uploaded, or relisted without the artist’s consent.

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### The Sui Shadow Solution

1. **Off-Chain Obfuscation**
   * Each artwork is divided into encrypted tiles. Full images never reside on-chain.
2. **Merkle-Backed Integrity**
   * A SHA-256 Merkle root of all ciphertexts lives in the NFT’s metadata, guaranteeing tamper-proof authenticity.
3. **Permissioned Decryption**
   * Only buyers—verified via a zk-anonymous credential—can fetch, verify, and decrypt tiles from off-chain storage.
4. **Gas-Efficient Minting**
   * On-chain data is limited to a 32-byte Merkle root and a few pointers, drastically reducing gas costs.

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### Key Technologies

* **Sui Seal**: Native on-chain encryption for sealing image tiles and coordinates, ensuring confidentiality before storage.
* **ZKlogin**: Zero-knowledge login and allowlist system that grants decryption rights only to verified buyers—no centralized authority or KYC required.
* **Walrus**: A decentralized off-chain storage network optimized for large media, hosting encrypted image blocks at low cost and high reliability.

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### Why Sui Shadow?

* **Authenticity & Integrity**: Any attempt to modify encrypted data invalidates the Merkle root, preventing tampering.
* **Privacy & Exclusivity**: Until purchase, viewers see only a blurred or watermarked preview—protecting the artist’s IP and maintaining scarcity.
* **Seamless UX**: Buyers fetch, verify, and decrypt all tiles in their browser, reassembling the full artwork client-side with zero trusted intermediaries.