## 4 Implementation
### Smart Contract
This was not explored further in this paper, as the goal was to minimize the dependencies between concerned parties. The proposed system opens up new potential for monetization of the game. The game developers could decide to shift part of their income from initial sales to configurable fees on each trade. This could revolutionize the Trading Card Games industry, potentially increasing user adoption by reducing entry price. Additionally, purely virtual card packs could be offered to users. This would enable them to later only print-on-demand the cards they use. This has two main benefits. As users' collections grow, it reduces the space required for storage. It also reduces the overhead of manufacturing and distribution of the packs, where usually at least half of the cards will never see play. This would require the game developer to provide such a print-on-demand system. Assuming a flat fee for each order plus the cost per card, it could still prove highly advantageous, and could be explored in future works. The downside of the system is that it is not backward compatible. The method of securing currently owned collections would be required to enable usage of the system with currently existing games. Alternatively, currently existing cards could be separated from the future ones and follow a slightly different set of rules. This would probably increase their physical value--as remnants of the physical-only era. Over time, collections would grow digitally and slowly replace purely physical mediums, delivering the benefits of the system. In the future, the protocol could be expanded to address the current centralization of system operators. In case the private key is lost, no more games can be added to the system. Similarly, if private key for the game is lost, no more collections could be added. Multi-sig solutions could be added, which would allow controlling given functionalities by the majority of keys from the designated pool. Conceptualization, M.R. ; methodology, M.R. ; software, M.R. ; validation, M.R. and M.N. ; formal analysis, M.R. ; investigation, M.R. ; resources, M.R. ; data curation, M.R. ; writing--original draft preparation, M.R. ; writing--review and editing, M.N. ; visualization, M.R. ; supervision, M.N. ; project administration, M.N. ; funding acquisition, M.N. All authors have read and agreed to the published version of the manuscript. Research was partly supported by the program \"Excellence initiative--research University\" for the AGH University of Krakow. Not applicable. The code for presented work can be found at [[https://github.com/Rakowskiii/TCGResearch](https://github.com/Rakowskiii/TCGResearch)]([https://github.com/Rakowskiii/TCGResearch](https://github.com/Rakowskiii/TCGResearch)) (accessed on 21 November 2024). ## Conflicts of Interest: The authors declare no conflicts of interest. ## References

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