Song That Plays When Somebody Verses Sans (Created for UNDERTALE 10th Anniversary Livestream)

I was asked by Toby Fox to contribute a few arrangements of UNDERTALE music for the 10th Anniversary Livestream, which was broadcasted on September 20th and 21st, 2025! It was an honor to get to make these arrangements, especially since I've made many UNDERTALE covers myself over the years. I contributed 3 songs for the Livestream, but this one, "Song That Plays When Somebody Verses Sans", is the battle music for the new Sans battle, which can be played in your browser for free! Extremely grateful to have had this opportunity to write this arrangements!

You can download this song, the rest of the 10th anniversary soundtrack, and play the new Sans and Mr. Sunshine & Abberant battles on the official UNDERTALE 10th anniversary website! https://undertale.com/10/

Happy 10th aniversary to UNDERTALE, and thank you all for supporting my UNDERTALE covers over the years!

Special thanks to @SkarnaesRa on Twitter for sending me their transcription of this song shortly after it was released, which really helped me record the footage of the walking bass part! https://x.com/SkarnaesRa

(This performance video was created with permission by Toby Fox, but not officially sanctioned or approved.)