A Layer 2 solution is just that, a solution to the problems common with older layer 1 blockchains. A layer 2 provides scalability & speed on networks with slow speeds and high transaction fees but at the cost of having a more centralized system with greater security risks.
There are issues introduced into the process when minting your NFT game assets on a Layer 2 blockchain. You can avoid those issues by building directly on Phantasma’s layer 1 blockchain, which was designed with high speeds and low transaction fees from the start.