Blockchain implementation

Layer 1 vs Layer 2 Blockchain

Layer 1 blockchains, such as Ethereum, are main and fully autonomous blockchains. They have their own network infrastructure, nodes, etc., making them more robust and secure than layer 2 blockchains. However, their scalability is limited, which can result in high transaction fees and longer confirmation times.

Layer 2 blockchains, such as Polygon, Optimism, and Arbitrum, are built on top of existing layer 1 blockchains like Ethereum. They are designed to be faster and cheaper than layer 1 blockchains, but they are also less secure because they depend on the underlying layer 1 blockchain's security.

A dynamic NFT is a type of NFT that can change state or content based on certain conditions. Unlike static NFTs, which have immutable properties, dynamic NFTs can be modified or updated.

For example, a dynamic NFT could contain information about the transaction history of a physical product, such as an artwork, or be linked to real-time events, such as in game challenge or IRL sport achievement.

Implementation in the game

The dynamics of dNFTs involve the importance of time-based events where players can unlock certain evolutions for their NFT. This evolution, once the event is over, can never be regained. (example: ascent of Mount Hiei during the Japan trip event) Another example: the dNFT of the first player to climb Everest will unlock a unique success and appearance. Planned in advance in the smart contract, a function that can only be executed once on a single dNFT.

To move off-chain data to the on-chain smart contract, an oracle is necessary. An oracle is a third-party service that provides off-chain data to a smart contract on the blockchain. In the context of dynamic NFTs, an oracle can be used to provide data that can trigger changes in the properties or appearance of the NFT. Chainlink VRF and Chainlink Contract Library are examples of oracle services that can be used to integrate off-chain data into the blockchain. Chainlink has the advantage of being available on several blockchains such as Ethereum, BNB, etc.

A potential issue with dynamic NFTs is the cost of paying the oracle every time it needs to provide off-chain information to the dynamic NFT's smart contract. This situation can result in additional costs for the user, which can be a significant disadvantage. Therefore, it is important to consider hidden costs when purchasing a dynamic NFT. To address this issue, one solution is to change the purchasing mechanism on the Everest marketplace. Instead of buying an already minted NFT, the user purchases the right to mint it themselves. By doing so, they can change the physical appearance of their climber at the time of purchase. This mechanism can also encourage them to buy via the Everest marketplace, and thus start the game from the beginning: without going through the marketplace, they will not be able to modify the appearance of their climber.