ULP-Swap: A Unified Liquidity Pool for Financial Reuse of Gaming NFTs via Pool Rentals and ABP-Secured Swaps

Abstract

Blockchain games provide verifiable ownership of in-game assets through nonfungible tokens (NFTs), but they still face high entry barriers, low capital efficiency, and fragmented asset liquidity across isolated game ecosystems. Existing NFT finance mechanisms remain largely separated: rental systems often require dedicated collateral or centralized coordination, while peer-to-peer swaps of unequal-value assets typically rely on additional balance margins. To address these limitations, we design a unified NFT liquidity and Swapping System centered on a unified liquidity pool (ULP). In our design, users deposit eligible NFTs into the ULP, and a time-weighted average price (TWAP)-based valuation module maps their deposited assets into a unified credit layer quantified by total borrowing power (TBP) and available borrowing power (ABP). This shared risk layer supports two application markets: 1) a pool rental market, where users access NFTs through their existing ABP; and 2) a peer-to-peer swap market, where the value difference in an unequal-value swap is secured by the lower-value party’s $\mathbf{ABP}_{\mathbf{net}}$ rather than an additional cash margin. We further present the protocol architecture, core accounting logic, and a prototype-level evaluation based on smart-contract gas analysis and multiagent simulation. Under the modeled assumptions, the results indicate improved rental accessibility, higher capital utilization, and reduced additional capital-locking requirements for NFT swaps, supporting the feasibility of more flexible financial reuse of gaming NFTs through a unified credit layer.