The current version of the game does not have multiplayer mode, custom levels and game background music. These features will be added in later updates. Also, Steam Trading Cards are coming soon.

Due to the time, I canceled the multiplayer mode.
I hope you will not be very sad, multiplayer mode will be released after the game is released through the game update.
Custom levels are not currently supported, but I've implemented a custom language and the game may support the Steam Workshop for you to upload custom language files.
Finally, thank you for waiting, if there is no problem, the game will be released this month.