Celestia is an RPG game heavily based off of Runescape, Minecraft, and The Legend of Zelda.
The majority of the scripts are commented and I am more than happy to help with any questions you may have!
NOTE: Celestia does not officially support GMS 2 but the engine still works after being imported. The game uses the get_string function when asking the user what their name is. This function is no longer in GMS 2 so you will need to modify where this function is used. Simply use CTRL-SHIFT-F to search for "get_string" and insert whatever name you want to use.
End User Licence Agreement (EULA).