In the banner above, I have pictured the 5 strongest examples of this visual motif as they appear in Undertale: Gyftrot (A random enemy encountered in the Snowdin Area), the DT Extractor (found in the True Lab underneath Alphys's lab in Hotland), Photoshop Flowey (The Final Boss of the Neutral Routes), Hyper Goner (The attack used in Asriel's fight in the Happy Ending Route to transistion from his 1st form to his 2nd form), and the infamous Gaster Blasters (Sans's signature attack used in his fight at the end of the No Mercy Route and very suspiciously seems to be named after Dr. W.D. Gaster).

For the purposes of my analysis, I define this visual motif as a snouted head with a mouth that opens along the vertical line of symmetry as opposed to along an upper and lower jaw which mouths are usually depicted with. It's worth noting that in it's "resting" state, the Gaster Blasters at first appear to be examples of mouths that open along the lower and upper jaw, but it's when they fire a laser attack we can see their lower jaw split to form an clear example of this visual motif.

For the sake of clarity, and also based on the objects I see this motif most strongly associated with in Undertale, I will refer to this as the Extractor/Blaster Motif.

Exhibit A: Photoshop Flowey

While this is not the first example of this motif you can encounter in the game, this is the most obvious example and definitely sets the stage for every other example of this motif that is seen in Undertale after this point. For those who need a refresher, this is the form Flowey takes at the end of the Neutral Routes where he absorbs the six human souls from Asgore's Castle, regains control of the ability to Save and Load the timeline of Undertale, and transforms into a being that is visually distinct, if not completely non-congruent with UT's usual early SNES-Era JRPG art style, thanks to the "photobash" style design created by designer Everdraed.

As this is the first defining appearance of this motif, there's not really many observations we can make at this point, especially since Photoshop Flowey's entire appearance is so alien and offputting in general. For our purposes, all we need to take note of is that Flowey takes on this form thanks to a large amount of SOUL power and as we learn more about the Human SOULs and Flowey, we can use this as a jumping off point the next time we see this motif pop up, especially in relation to SOULs and Flowey.

Exhibit B: The DT Extractor

Now here's where things get interesting. In the The True Lab, we learn about Alphys's experiments with "Determination" and among other things, learn how she used the DT Extraction Machine to extract Determination from the 6 Human Souls and apparently gave Flowey sentience and the will to live when she injected one of Asgore's golden flowers with Determination. This already makes a lot of things fall into place, namely, Photoshop Flowey's and the Extractor's visual similarities with the most obvious being the metallic pipes and a very familiar silhouette.

To talk about the design of the extractor itself, it's snout to me looks a lot like insect mandibles and the two hollow openings that creates it's "eyes" also remind me of Plague Doctors and the masks we associate with them in Pop Culture. All-in-all, this design is definitely a solid sinister-looking machine of some type and will probably remind players of their fight with Photoshop Flowey.

Based on the two examples we have at this point, it seems that Photoshop Flowey's distinct appearance is related to how he extracted the power of the Human Souls. Going forward, it also becomes pretty clear that Flowey tries to recreate situations from his past as a manisfestation of his twisted nostalgia, and I personally interpret Photoshop Flowey's visual similarity to the DT Extractor as an example of him recreating (conciously or subconciously) an important symbol from his past, in this case, the very machine that facilitated his revival in the first place.

There's one last thing I feel is worth talking about in regards to the DT Extractor and thats in one of Alphys's Lab Entrys that you find before you see the DT Extractor, she talks about how she was following blueprints to faciliate the extraction of Determination but it's been left somewhat ambigious on whether or not these blueprints were designed by her or another scientist in Undertale's world, which will come back in some speculation after I introduce Exhibit D.

Exhibit C: Hyper Goner

After the True Lab arc, Flowey once again absorbs the 6 Human Souls this time along with almost every soul in the Underground to help him revert back his previous identity of Asriel, the fallen prince of the Underground who befriended and adopted the first fallen human (AKA "Chara") as his sibling. In his fight in the Happy Ending/True Pacifist Route, at the end of his 1st phase (where "Hopes and Dreams" plays), he uses an attack called Hyper Goner where he summons a giant goat head that absorbs nearby particles and debris. To be honest, this attack on it's own is probably the weakest appearance of this motif we'll talk about, but the connection will become a bit more obvious when we start talking about Exhibit D next.

Design wise, the Hyper Goner attack really just hammers in Asriel's association with Satanic Goat imagery, though I do find it kind of interesting how the horns and ears on this specific sprite seem reminiscent of Flowey's flower petals.

One other thing that is worth noting about Hyper Goner is it's name. "Goner" is a name associated with the Fun Value exclusive NPC "Goner Kid" and the opening sequence in Deltarune where you're asked to create a Vessel is also referred to in the metadata as the Goner Maker. In the case of Goner Kid, they talk about a dilemma they have about living in a world that's exactly the same, except you don't exist yet everything functions perfectly without you. This seems to imply that Goner Kid, and possibly the other Fun Value Exclusive NPCs (like the Gaster Followers, Clam Girl and the Mystery Man) exist outside of Undertale's reality; perhaps even the bounds of the game based on Goner Kid's use of the word "functions".

Once again, Asriel has reclaimmed the power to interact with Undertale's world like a video game as the Determination of the 6 Human Souls and every monster in the Underground allow him to SAVE, LOAD, and RESET, so maybe the Hyper Goner attack is meant to send you to this same "Goner" state the other Fun Value NPCs are in. I don't have any definitive evidence to support my claim, but given how Goner as a term reappears in Deltarune in a different context, I think it's fair to take note of whenever this term appears, especially in situations where the walls between Undertale the world and Undertale the game seem to be crumbling down.

Exhibit D: Gaster Blaster

This is perhaps the most infamous instance of this motif and Undertale so lets just dive right into it. In Sans's equally infamous fight at the end of the No Mercy Route, Sans employs one attack that is completely unique to him and isn't just building off of the bone-shaped bullet patterns and Blue SOUL mode used in his brother's Papyrus's fight and thats these skeleton dragon death laser things that everyone in 2015 thought was the coolest shit ever and even despite overexposure, those people are still mostly right. Unlike Asriel, Sans and all of Undertale's other characters never have their attacks given names that we can see in the Fight UI Text box so they would've gone unnamed if we didn't have metadata on our side. However, because we're talking about Undertale/Deltarune here, we get some very crucial information here that really raises a lot of alarm bells and that's because Sans's signature attack are called "Gaster Blasters" in the game files.

If you need a refresher on what "Gaster" implies and why he's greatly important to this analysis, check out my Video Game Mysteries page and the section on this character just so I don't have to do a complete explaination of everything that's going on with this guy and we can get on to where I can talk about some speculation.

Anyways, aside from the Gaster revelation, this instance of the motif is still peculier mostly in that this is the first time we've seen it come up in a context seperate from Flowey, which raises some interesting questions. If Flowey is no longer here to tie the threads together, than what is the use of this symbol here supposed to mean?

oops sans skillset analysis and speculation (not essential to main topic)

Sans is a very nebulous character in that unlike Flowey, Chara, Frisk and the Player, he seems to not have the context that Undertale is a video game, and his way of explaining the latter characters use of the power to interact with the SAVE file is that it's a form of time travel that he rationalizes with a scientific perspective. Despite this very clear knowledge gap, Sans still seems to operate in a level above the other residents of the Underground mainly with the ability to read the Player's/Frisk's Level Of Violence and EXP, take "shortcuts" that allows him travel across the game's maps without moving, can attack the Player's soul in his fight even when it's not his turn by attacking the UI, cause the screen to flash, and prolong his battle turn at least as long as he stays awake. Papyrus seems to have some of these abilities too, and most of the times we see Sans and Papyrus do stuff like this, it's mostly for the sake of gags, almost like they run on cartoon logic.

My gut reaction for why Sans is the only character in Undertale with these specific capabilities is that it has to be something Gaster related. My best guess for why Sans can interact with the world on a different level than the other residents of the Underground while still being completely oblivious of the SAVE file is that he's maybe able to walk the line that seperates the rest of Undertale from the Fun Value NPCs? I'm hesitant to go down this road because it brings to mind a lot of fanworks that attribute Sans getting these abilities from whatever went down in Gaster's experiments and while I don't think it's impossible, I do feel like I owe it to Sans, who at his core is just trying to be "some guy", to look for an answer that isn't just a dramatic origin story yet to be written.

From that train of thought, maybe Sans has always had these gamebreaking abilities and that the extent of these are informed by his unique personality. Something that gets overlooked about Sans is that he can be a bit of a harmless con-man at times (like trying to sell you Fried Snow on your way to Snowdin and running the Casino in the various console ports of Undertales) which shows that maybe there's something to Flowey's accusation of him being a "cheater"; like the type who'd purposefully deal you a bad hand in poker and that he's willing to bend rules and break promises in a way that characters who are objectively stronger and more determined than him (Toriel, Papyrus, Undyne, etc...) aren't willing to.

Actually, if Sans is a character who is just kind of "gamebreaking" by nature, that would draw an interesting comparison to Noelle from Deltarune who loves glitch hunting in video games which has harrowing consequences when you realize she lives in a video game and has her own Gaster connections. I'd love to see if the future chapters of Deltarune do anything with this idea...

One last Sans thing I find fascinating is that he's the only enemy that utilizes the "Karma" mechanic which is essentially just the Poison status effect you'd find in other JRPGs just with a much more evocative name. My guess is that the "Karma" mechanic is tied to Sans's role of judge and that he's...somehow able to leverage the Player's Execution Points against them like what the whole "You feel your sins crawling down your back" seems to evoke.

I don't think it makes a lot of sense for Sans to have a particularly high amount of Determination, so I don't think that Gaster Blasters have anything to do with that. My guess is that if there's anything the motif is meant to imply is that the Blasters has something to do with SOULs in general, specifically, Sans's role as judge and the way he can interact with SOULs.

Focusing back in on the design itself, the design of Gaster Blasters is clearly skeletal and they all have the same wide smile that Sans is strongly associated with. I've seen alot of analysis over the years over what specific animal skull the Gaster Blasters are from, and the example I've personally seen the most often is turtle skulls, which is kind of interesting since Undertale does have some minor NPCs based on turtles that have a history in Undertale's (and Deltarune's) lore, but I personally can't say that the Gaster Blasters are meant to be any real-life animal and to me just look like a cool monster design.

Exhibit A, B, C, and D: Synthesis

I want to take a moment now to talk about Photoshop Flowey, the DT Extractor, Hyper Goner, and the Gaster Blasters in relation to each other, specifically the continuity I think exists between each of these versions of the Extractor/Blaster Motifs as a way to help set the stage for Exhibit E.

Gaster Blasters -> Hyper Goner

I mentioned in the DT Extractor section that Flower/Asriel likes emulating people from his past and there's been cases made that Asriel as the God of Hyperdeath was emulating Sans a bit in his fight. Flowey as a Player analog has done No Mercy Routes and he has fought the Sans though has apparently given up before he could he beat him. The Hyper Goner as this whole analysis asserts shares an obvious visual connection to the Gaster Blasters and Asriel does the same cocky shrugging gesture that Sans does in his fight. Seeing how Asriel seems to be evoking JRPG Final Bosses in his final fight in general, to me, it makes a lot of sense that he would try emulating his personal own Final Boss.

Gaster Blasters -> DT Extractor

Again in the DT Extractor section I talked about the blueprints Alphys used to build the machine and I am one of those sickos that thinks Gaster made the original blueprints based on his Gaster Blasters and that the DT Extractor concept was abandoned after he started working on whatever invention caused him to discover the Dark Worlds. Like most things Gaster related, I don't have any strong evidence for this other than it'd make my preconcieved notions fall into place, so please take this with a grain of salt.

Exhibit E: Gyftrot

While Gyftrot is in fact, the actual first appearance of the Extractor/Blaster motif we can find in Undertale, it's also the odd-man-out in that Gyftrot is not a narratively significant character and is in fact a random enemy you can encounter on the road to Snowdin, though it is found the outside cave where the Mysterious Door is, which only opens after dodging all the Kickstarter Backer Names during the Happy Ending/True Pacifist Ending Credits. However, like several other "random enemy" characters in Undertale, we do know that Gyftrot has a bit of a backstory in that the teenage monsters around Snowdin keep decorating them like a Christmas Tree which is why they're initially hostile towards Frisk.

Gyftrot was originally designed by Magnolia Porter for the Hotland area, having their antlers spout flames instead until Toby requested to move Gyftrot to the Snowdin area, thus the change to it's festive Christmas theming.

...Which is significant in the context of "Delatrune" which introduces a family of holiday-themed Reindeer who do not have the Extractor/Blaster motif but are very narratively significant to Undertale's follow-up. Unfortunately, I don't think that that can tell us anything more about Gyftrot in Undertale nor has any deeper signifcance at this point, but for the sake of comprehension, I did want to make note of it here in case the Extractor/Blaster motif makes an explicit reappearance in Deltarune in relation to Noelle Holiday and her family.

Conclusions

So unfortunately, this analysis did not really help me answer any Deltarune hot topics, but at least now I think we have a pretty comprehensive list of this Visual Motif that I hope explains why even the less obvious appearances of this motif like the Gaster Blaster still fit this criteria and can be used to make comparison based analysis.

So my gut reaction for why we have so many repeated appearances of this type of design in Undertale likely has something to do with vertical mouths invoking a natural "Uncanny Valley" response from general audiences and helping sell that Undertale's setting is a world of monsters and the supernatural. It seems to be very to similar to why the "Smile Motif" is so prevalent throughout Undertale and Deltarune.
(If you want to learn more about that, check out HalfBreadChaos's video on that topic)

Based on our examples in Undertale, I feel that the Extractor/Blaster motif is most strongly associated with SOULs, Determination and Flowey/Asriel. To me, the Gaster Blasters complicate this the most, as unlike Gyftrot, the Gaster Blasters are not just narratively signifcant, but are deeply suspicious due to their association with Undertale's most nebulous and mysterious characters. It's almost to the point where I think that maybe the motif's appearance here was kind of incidental and happened on accident when whoever was animating the Gaster Blasters was trying to animate the laser blast motion.

My hope is that Deltarune will build on this motif just like it has been doing with the "Pie", "Knife" and "Smile" motifs that will help us flatten out this wrinkle. Of course, I'd love it even more for this unique design trope to come up in a new and exciting context! For as much as people talk about Undertale's art being purposefully primitive, there was clearly a ton of thought put into its visual symbolism that enhances the written narrative, musical continuity, and unqiue gameplay that make this game so fascinating even 8-9 years later. Feel free to reach out to me if you have your own thoughts on this motif, I'd love for this to branch out into some larger discussions as we wait for more chapters of Deltarune to be released!