Unwrapping ERC-20s

Overview of steps needed to unwrap ERC-20s & Chia-side initial transaction model

Unwrapping ERC-20s is initiated by burning wrapped ERC-20 CATs on Chia by building and submitting a spend bundle as depicted above. This operation generates a message coming from a trusted 'CAT Burner' puzzle, which can then be relayed to the destination chain. After the user calls the portal's receiveMessage function, the message will be relayed to the ERC20Bridge contract (message destination), which will send the equivalent amount of ERC-20 tokens (minus the bridging tip) to the destination address that was specified when bridging was initiated on Chia.