His Theme

"His Theme" is the 90th  in the Undertale Soundtrack. It plays during the final part of the fight with Asriel Dreemurr, as soon as Asriel Dreemurr has a flashback of when he first found the First Human. It is a solemn, emotional song which is actually an orchestrated version of "Memory".

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It is only used once during the funeral of Lucida in a flashback where Asriel uses it to express his sadness

The Song
https://www.youtube.com/watch?v=IkOK8tdEsFY