Game Channels for Trustless Off-Chain Interactions in Decentralized Virtual Worlds




Huntercoin, Virtual reality, Blockchain gaming, Payment channel, Off-chain interaction, Smart contract


Blockchains can be used to build multi-player online games and virtual worlds that require no central server. This concept is pioneered by Huntercoin, but it leads to large growth of the blockchain and heavy resource requirements. In this paper, we present a new protocol inspired by payment channels and sidechains that allows for trustless off-chain interactions of players in private turn-based games. They are usually performed without requiring space in the public blockchain, but if a dispute arises, the public network can be used to resolve the conflict. We also analyze the resulting security guarantees and describe possible extensions to games with shared turns and for near real-time interaction. Our proposed concept can be used to scale Huntercoin to very large or even infinite worlds and to enable almost real-time interactions between players. 

Author Biography

Daniel Kraft, University of Graz

D. Kraft ( is a mathematician and the current Huntercoin main developer


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Additional Files



How to Cite

Kraft, D. (2016). Game Channels for Trustless Off-Chain Interactions in Decentralized Virtual Worlds. Ledger, 1, 84–98.



Research Articles