Mettaton

Mettaton
Mettaton is Dr. Alphys's robot and the main antagonist in The Mettatonation War. He is made of metal and magic and seems to be programmed to have a soul. During Squadward's Calamity, Mettaton found out that Undyne was defeated on the battlefield by Squadward's army. After her defeat, Mettaton remixed her song again and wrote a book on her failure.