An analytical video exploring Dr. W.D. Gaster, his lore, theories, and how the fanon surrounding him has created a mandela effect within the fandom, blurring the line between fanmade and canon. This focuses primarily on Undertale rather than his role in Deltarune. We’ll cover the fun events, the Gaster followers, Gaster’s relations to other characters, and how he casts an unfair shadow over Alphys.

Special thanks to anonymouse for providing me w/ saves and helping w/ capturing footage as well as I’m an Issue for the Gaster stats.

My Patreon:
My Ko-Fi:
Go-Fund Me for Sewer Costs:
Twitter Mirror for signal boosting:
Inverted Fate:


0:00 – Introduction
1:03 – The Void
2:24 – What the Gaster Followers Say
3:35 – Gone But Not (Necessarily) Forgotten
6:10 – Mysteryman and Gaster
7:47 – Skeleton and Sans
9:51 – The Determination Experiments
11:35 – Closing Observations
13:05 – Emergency Situation

If you wish to see a more Deltarune-focused video, check out Misty Sparkles’ video here:
DR Failsafe Text Origin:
Redacted and Soundtest Footage source:
Goner Clam Footage:
Gaster fan battle source:
Darker Yet Darker:
Dogs of Future Past:
Call of the Void trailer:
Ask Frisk and Company:

All fanworks showcased were chosen mostly to emphasize how prominent Gaster is in the fandom. Please do not use this video as an excuse to attack the creators.

#Undertale #Gaster #WDGaster #W.D._Gaster #Gaster_Theory #Undertale_Theory #UndertaleTheory #Mysteryman #Sans #Determination #CORE #The CORE #UndertaleGaster