Underbattle is a free Android game developed by Sukirii. It is a fangame based on the popular game Undertale, where you fight multiple bosses, buy upgrades and more. The game is categorized as a role-playing game and is available on the Google Play Store for Android devices.

The game uses Unity's default Ad, which is only for test purposes and doesn't generate any revenue for the developer. The music used in the game is not owned by the developer and the credits are given to Toby Fox, Nitro Fun, Big Giant Circles, Tristram, Chipzel, and Kubbi. The gameplay is similar to Undertale, with the player taking control of a character and fighting bosses to progress through the game.

Overall, Underbattle is an enjoyable game for Undertale fans, with its easy-to-use interface, fun gameplay, and great music. The only downside is the presence of ads, but since they are only for test purposes and don't generate revenue, it's a minor inconvenience.