Gaster Effect

The Gaster Effect (Undertale term) is when a person mistakenly links anything slightly mysterious, or anything slightly resembling Gaster (leitmotifs, font or face) relating to Undertale or Deltarune, to the character W.D. Gaster, even if it is very hard. This is usually because Gaster is very mysterious and of a certain significance to said games' lore. In most cases, relating things to Gaster is not appropriate for the situation and/or possibly misleading.

A: Woah that new Deltarune song has Gaster's Theme playing at 0:44! If you listen to the piano...
B: Those are just arpeggios. You've got the Gaster Effect

by Stratollera April 15, 2024

Gamster Kitpvp War I

In Gamster, kitpvp war III Xaw, was a very powerful clan with a lot of cheating retarded niggers. Their leader being the most deadliest Miyahi. They owned kitpvp for more than 6 years. They were deemed unbeatable. Only a few clans were able to defend themselves against xaw. Such as SENT, SENTINELS QD, QUICKDROPPED and lastly NDBF NODEBUFF. Those clans were the highest in power. But they didn't stand a chance against Xaw. Untill one clan showed up. This clan was growing up so quickly it was catching Xaw's attention. Then 2023 Event Horizon steps in. With its leader being Burhh, A former Mineberry Legend. Destroying both Xaw and QD The most deadliest clans on Kitpvp ever. Miyahi and Andreeeeew The QD Leader Were fuming they fought and fought but. Event Horizon was always the one that finished on top. After a while of battling each other over and over Xaw, The clan known to be the most deadliest and most feared was banished by Event Horizon. QD was able to withstand Event Horizon's wrath but not for too long. 2024 QD, crumbles into pieces of dust to Event Horizon and QD was gone for good. Then Event Horizon continues to destroy more clans and win a few squidwars here and there. They all have sex together especially with their Leader Burhh, and his pupil Rayloss. They fuck and cum everywhere! untill Event Horizon slowly falls down. But they did not lose a single battle after defeating the most deadliest clans in the kitpvp world. They were legends upon the kitpvp community.

Yoooo. did you know that this RETARD fought in Gamster kitpvp War I ?!
Lol stupid veezra imagine losing in Gamster kitpvp War I

by ray4c June 16, 2024

Gasterbating

A term that is commonly used among gooners, where you are gaslighting people online with false information or 10/10 ragebait and pleasuring yourself to their reactions. This is commonly used in social media platforms such as reddit, twitter (mainly), and instagram.

Peak gasterbaters have content farms with bots sending 100s of false information on post, or just normies that just want people to rage.

Hey tommy i tried gasterbating last night. i gasterbated so hard the furry on twitter killed themselves can you believe that?! i nutted so hard on my computer screen when i found out.

by ABuildingOnFire June 17, 2025

Gasterbating

masturbation to or sexual attraction to the character W.D. Gaster from Undertale

does W.D. Gaster have any results on rule 34?

damn it now i'm Gasterbating

by chronic gooner June 18, 2025

Gaster

A mysterious figure talked about in the game UNDERTALE made by Toby Fox through entities called "Gaster Followers". Gaster Followers can only be obtained through getting certain numbers on an RNG system called "FUN value." The Gaster Followers will hint at what Gaster was and what he did. A hallway can appear in the Waterfall area if you have a FUN value of 66, but there is a 10% chance while have FUN value 66 that a mysterious door will appear. An entity is spotted when going through the door. It is highly speculated that this person might be Gaster, as when you interact with him, he plays a sped up and reversed version of Gaster's Theme

"Gaster? Who is that? I've never heard someone with that name before.."

by personusingtheurbandictionary September 6, 2025

Gaster

A man who listens

But rarely speaks

Susie: Oh my full name? It's Susie Gaster-
Once upon a time, a LEGEND was whispered among shadows.
It was a LEGEND of HOPE.
It was a LEGEND of DREAMS.
It was a LEGEND of LIGHT.
It was a LEGEND of DARK.
This is the legend of DELTA RUNE
For millenia, LIGHT and DARK have lived in balance,
Bringing peace to the WORLD.
But if this harmony were to shatter...
a terrible calamity would occur.
The sky will run black with terror
And the land will crack with fear.
Then, her heart pounding...
The EARTH will draw her final breath.
Only then, shining with hope...
Three HEROES appear at WORLDS' edge.
A HUMAN,
A MONSTER,
And a PRINCE FROM THE DARK.
Only they can seal the fountains
And banish the ANGEL'S HEAVEN.
Only then will balance be restored,
And the WORLD saved from destruction.
Today, the FOUNTAIN OF DARKNESS-
The geyser that gives this land form-
Stands tall at the center of the kingdom.
But recently, another fountain has appeared on the horizon...
And with it, the balance of LIGHT and DARK begins to shift...
DELTARUNE

by Bonkaaaaaaaaaaaaaaaaaaaaaa December 9, 2025

Gaster Bullshit

"Gaster Bullshit" is when a game has major fourth wall breaks, ARG links, hidden mysteries, or anything other elements that could be compared to W.D. Gaster. Also used for any sketchy shit going on in Deltarune that probably connects to him.

"I heard oneshot had a bunch of gaster bullshit so i had to give it a try"

"WHAT DO YOU MEAN THE KNIGHT HAS HOLES IN ITS HANDS??? THIS IS GASTER BULLSHIT BRO"

by ElliottLava January 10, 2026