For the Mus_Smile spectrogram.
Thats NOT GASTER. But a hint towards it.
We officially might know how Napstablook s'cousin looked like before he became Mettaton...
How do i know this might be him?
He looks like napstablook but in different colors and HAPPY.
Papyrus calls him Hapstablook.
Papyrus is one of the skeletons... And gaster might be one.