Undertale 1 by Firefox user 11642616

Undertale was created by Toby Fox.
http://undertale.com/
ORIGINAL ART:
-Sans by SecretMetalAlchemist http://secretmetalalchemist.deviantart.com/
-Frisk and Chara by CoolGuyEnzo
-Alphys and Napstablook by Evomanaphy
http://evomanaphy.deviantart.com/
-Papyrus and Undyne by Rittesora
http://rittesora.tumblr.com/
-Annoying Dog by iamnotamuffin
http://iamnotamuffin.tumblr.com/
-Flowey by Xamag
http://mtt-brand-undertale.tumblr.com/
-Mettaton by marreeps
http://marreeps.deviantart.com/