Hey Nemquae -- awesome! Look forward to hearing more about this as it develops.
In regard tag authenticity, bitbind.io supports this through namespaces -- every tag written is prefixed with a namespace associated with your API keys. So, for example, any Deckbound object or tag will return with the "deckbound:" prefix, which can only be written by the owner of the Deckbound API keys (which is the Deckbound system itself).
For bitbind.io, we're looking to expand the ownership to be tied to private keys themselves -- i.e. you could authorise a key change by signing a transaction.
Another system that might be interesting to explore would be a forked namespace model, where a user who wished to branch from the canon could do so by declaring a namespace as a fork of another. How you dealt with this at a game level would very much depend on your game systems, but it's an interesting approach and well proven by DVCS practices.