Undertale 10th Anniversary is a short web-based game that celebrates 10 years since Undertale's release. It focuses on two isolated battles: one against the duo Mr. Sunshine and Abberant, and another against Sans.
CasualPokePlayer completes both battles as quickly as possible.
This Web publication was made possible by unofficially porting the webgame to Linux, as it's a GameMaker game, and TASing it on libTAS.