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NFT Minting

Catpound NFTs live on OPNet as OP721 tokens. To bring a Bitcoin Ordinals collection on-chain, Catpound uses a death lock + OP721 mint flow. This page explains how it works.

Overview​

Bitcoin Ordinals (inscriptions) exist on Bitcoin L1 but are not natively readable by OPNet smart contracts. To use an Ordinal for vault tier upgrades, it must be bound to an OPNet OP721 NFT. The process permanently locks the Ordinal in exchange for an on-chain OPNet NFT with matching metadata.

The Death Lock​

A death lock is a one-way binding that permanently locks a Bitcoin Ordinal to a specific unspendable address. Once locked:

  • The Ordinal can never be moved or sold on Bitcoin again.
  • A corresponding OP721 NFT is minted on OPNet, linked to the original inscription ID.
  • The OP721 NFT becomes the canonical representation of that Ordinal within the OPNet ecosystem.

This is an irreversible process by design -- it prevents double-spending (using the same Ordinal both on Bitcoin and on OPNet simultaneously).

Mint Flow​

  1. Select your Ordinal: Choose a Bitcoin Ordinal from an eligible collection (e.g., Motocats) in the Catpound NFT Mint page.
  2. Initiate binding: The app sends the Ordinal to a death lock address via a Bitcoin transaction. This address is derived deterministically and is provably unspendable.
  3. Relayer verification: The Catpound relayer monitors the Bitcoin chain for the lock transaction. Once confirmed, it verifies the inscription ID, collection membership, and lock validity.
  4. OP721 mint: The relayer triggers the OPNet NFT contract to mint an OP721 token to your OPNet address. The token carries the original inscription metadata (ID, collection, traits).
  5. Done: Your OP721 NFT appears in your OPWallet and can be staked in the Catpound vault for tier upgrades.

OP721 Standard​

OP721 is the OPNet NFT standard, analogous to ERC-721 on Ethereum. OP721 NFTs support:

  • Ownership tracking: Each token has a single owner address on OPNet.
  • Transfers: NFTs can be sent between OPNet wallets.
  • Contract interactions: Smart contracts (like the Catpound vault) can hold, transfer, and query NFTs programmatically.

Motocats​

Motocats are the first Ordinals collection eligible for the death lock + OP721 mint flow. Once minted as OP721 tokens, Motocats can be staked in the Catpound vault to unlock lower fee tiers.

See NFT Staking for details on how staked NFTs reduce your fees.