Hello! You can buy the bundle here https://itch.io/s/61376/epic-rpg-world-bundle-
The Ancient Ruins asset pack will be part of another pack with the next two other packs that I'll release soon('Sewers' and 'Prison'). The reason behind this is because I think just one bundle with all the packs would be too expensive for many.
Yes, the asset is yours forever and you can use it commercially in your game. If you lose the files in your computer for some reason, you can just access my store and download it again.