Very inexperienced developer, I recommend you try personal projects prior to posting resources on Spigot. The resource does not even attempt to connect to MySQL while it still prompts you for it in the config. The name "Cubecraft core" has nothing to do with it and is click bait. Updater class is blatantly copied without proper credit, etc. The only real feature of the resource is a join message that gives the information provided in the config.