Non Fungible Mutable Tokens: dynamic assets traceability for the Metaverse

In this paper we focus on the mutability of NonFungible Tokens associated to digital assets in the metaverse.We argue that mutability is a key property of digital assetsif we want to provide users with a virtual experience in themetaverse as close as possible to the real world. We discuss theshortcomings of current dynamic Non Fungible Token proposals,and present the advantages of a new mutable Non FungibleToken approach based on decoupling the asset ownership anddescriptor in separate smart contracts. To show a possible usageof mutable Non Fungible Tokens in a metaverse, we provide areference example about a university gadget. Finally, we presenta proof of concept implementation of our reference example onthe Decentraland metaverse and the Goerli Ethereum testnet toshowcase its feasibility.