アンギラス

That Anguirus is a dinosaur mutated by atomic tests is clear, but the specific tests and kind of dinosaur aren't. That second one seems obvious enough because if you watch a proper subtitled version or just happen to know how they got that name, you'll likely be pretty confident that Anguirus is an Anylosaurus. And you would be wrong, because that's not possible for two impossible to ignore reasons: 1. No animal genus in all of history has survived that long unchanged, and 2. Every single aspect of Anguirus is completely incompatible with that idea. This isn't the end of the world, of course, because the only person who actually makes this claim in the series is Dr. Tadokoro, who is well established to be a hack fraud idiot that has no idea what the hell they're talking aboot, and they probably got their degree from the back of a Cracker Jack box. In the real world, this is exactly equivalent to how in an earlier draft of Godzilla vs. King Ghidorah Godzilla was written to be a mutant Tyrannosaurus before someone with a single brain cell looked at that and realized they were going to make flat earthers look smart. The solution to this is equally simple: there are no surviving non-avian dinosaurs in real life, so whatever Anguirus was before mutation is also going to be a monster no matter what, and evolution even at its slowest never sits still, so whatever that monster is it isn't an Ankylosaurus regardless of if it descended from them or not. Notably, the timeframe given for the animal doesn't match the real fossils even when adjusted for the fact that the movie was filmed in the 50's. That alone proves that whatever the hell Tadokoro was talking aboot it sure wasn't Ankylosaurus specifically.
     Here I've taken the liberty of referring to this unseen genus of dinosaur as Anguillosaurus, which is how people have taken to writing the hilariously inept line flub in Gigantis where the guy dubbing Dr. Tadokoro tries to say "Ankylosaurus" while gargling an entire jar of marbles. Since Anguirus has never gotten the same treatment Godzilla did, we can't say a whole lot aboot this "Anguillosaurus" for sure, but we do know some things that are extremely bizarre. Number one with a bullet, Anguirus has predatory teeth and of all the load of bullshit Tadokoro shoved down our throats, the notion that our natural Anguirus species is predatory and terratorial actually holds up as at that point there's really no other reason for it and Godzilla to be fighting. We also know that they are adept swimmers and can burrow as well. Both of these are completely unheard of in Ankylosaurs with any real certainty, but interestingly the superficially similar turtles have an old hypothesis aboot their origins which connected them to fossorial adaptations in animals like the Permian Eunotosaurus. Now I'm not going to get into turtle hypotheses here because that's above my pay grade, but that there's a historical example of fossorial adaptations being potentially useful for aquatic adaptations gives us a look at what we might hear if Dr. Yamane still had some of his soul intact so he could come up with an equally compelling hypothesis for Anguirus's ghost lineage as he did for Godzilla. After all, we know that he got it right for Godzilla.
     Taking it back to dinosaurs for a minute, I've always been of the opinion that the animal Anguirus was originally wasn't an Ankylosaur at all, but rather a very basal Thyreophoran that pre-dates the split between Stegosaurs and Ankylosaurs. The way I figured was that you could easily lose the tail club if Anguirus wasn't just a Nodosaurid, but the teeth, face shape, terratorial attitude, etc., stuck me as the most important detail because it really did suggest that pre-mutation it was at least somewhat predatory. I didn't know of any examples of very derived herbivores evolving the other way, and I couldn't think of a compelling environment that would push the situation, so I thought chances are Anguirus's ancestors branched off early when Thyreophorans were basically just really spiky Heterodontosaurs. However, the real world has brought us an even more likely starting point: the early Cretaceous Liaoningosaurus, which actually did live within the time span given by Dr. Tadokoro's children's book. From the name you can tell it's Chinese, which puts it in mainland Eurasia with Siberia, but the real fun part is that based on the presence of fish remains under the stomach of a nearly complete specimen led to the hypothesis that it was both semiaquatic and carnivorous. Obviously there's more to it, that's a pretty insane thing to throw out for an Ankylosaur and they do back this up a little harder than that, and of course there's plenty of counterarguments for all of that, but the fact that a bunch of professional paleontologists looked at this stuff and did the work and considered that to be a reasonable conclusion to publish academically says a lot. And honestly the more you read aboot why they think this the more it sounds like they're just writing a paper on Anguirus, it's honestly eerie. Now the reality seems to be something along the lines of a lot of the features suggesting swimming or predatory adaptations may actually be an ontology thing and indeed other Ankylosaurs have been found nearby which seem to be slightly older animals, but even that's serendipitous for us because it gives us an obvious jumping off point. Not only do we know where Anguirus's ghost lineage began, but we even know HOW it started: neotony. If juvenile Liaoningosaurus have adaptations that could benefit swimming and predation, then the clear path to Anguirus is that they just selected for retaining those juvenile traits for longer and longer. So we don't really know for sure what Toho's thinking with Anguirus here or if they'll ever deliver on this mysterious pre-Anguirus the same way they did for pre-Godzilla, but at the very least coincidence has already handed us most of the story on a silver platter. So, there you go, there's your Anguillosaurus, the logical conclusion of one of the wildest Ankylosaur papers ever written.
     As for the other unknown, which tests are responsible for each Anguirus, that will differ by individual and so you can check the notes for more detail on my speculation on those matters.

The most Anguiri any of the timelines of the Godzilla series has is the AniGoji timeline which according to the prequel novels maxes out at four. Of these, there is a Pacific and Siberian Anguirus, both of which match up with Anguiri seen in the Showa continuity, one is from South Africa, which correlates to nothing from the films, and the last is never elaborated on, we only know it exists because the Pacific one is called "Anguirus IV." The Anguirus from Final Wars is, like everything else in that movie, completely gutted of all context that may or may not have been present in earlier drafts. It could really go either way on this, but for a full elaboration on why I've filled out this chart the way I have, see the notes for the 3rd generation Anguirus.

初代アンギラス • 1st Generation Anguirus

Height: 60 meters
Length: 100 meters
Weight: 30,000 tons
Abilities: Incandescent Light, Ultrasonic Roar, Spiked Carapace

History: The original Anguirus found its way from Siberia to Iwato Island in the Pacific Ocean somehow, where it found itself in conflict with Godzilla (2nd). The two tussled but fell into the ocean and went their separate ways. Later, a huge fire in the Osaka industrial park drew Anguirus' attention, drawing them towards the city where Godzilla had already appeared. The two fought to the death inside the city, specifically Anguirus' death, as the monster was burned alive by Godzilla's atomic breath.

Notes: Despite it being well established that Godzilla was the product of the US's Castle Bravo test, specifically, this level of specificity isn't very common for most of the series, and most Toho monster movies are perfectly content to just vaguely handwave the reason monsters appear as "because of all the radiation." I'm less content with that, however. In the case of Anguirus we have two individuals in the Showa timeline and according to promotional materials of the time we at least can say the original was the result of Soviet testing in Siberia. How Anguirus got to the middle of the Pacific Ocean before being noticed is unclear, but remember that the USSR was extremely secretive at the time, these are the same dudes who erased people from photographs. So imagine that it's 1954, Godzilla's box is opened, and, uh oh, your irresponsible use of nuclear weapons has just created another monster. You are now at least equally as responsible for bringing mankind into the age of monsters as your primary economic, scientific, military, and ideological rival, the US. The solution? Well you just don't tell anyone about that, either. Erase Anguirus from the photographs, or just burn them. Officially? Officially Anguirus was first sighted in the Pacific Ocean, that's the story. Given the 2nd generation was seen burrowing, this actually fits into place perfectly, if the USSR did see and potentially attack Anguirus, it might have just burrowed away, andd the Soviets might have believed they just killed it. Officially? The USSR may not consider their monster problem which they officially never had to begin with to even BE the same Anguirus from Iwato Island. I've always loved this weird little piece of information because it's a really clever way to make a Cold War I era Godzilla movie resonate by having not only the US tests create monsters, but the USSR tests as well, literally putting Japan square in the middle of the two monstrous superpowers. If it was actually in the movie, it would be all the better for it, but alas, it's just a fun fact in the theater program.
     Anwyas, there's no way the filmmakers could've planned aroond a specific Soviet nuclear test because... well, they were all classified, duh. US intelligence was keeping track, but again, the US wasn't really sharing that kind of information with Toho. Of course, now it's all public information and you can look up every single nuclear test on wikipedia. So, retroactively, based on the tests that have been unclassified with time, we know that Anguirus couldn't be the product of any test done in 1955 given that the earliest done by the USSR that year was in July, and the film picks up in January. The last test prior to the film happened in the Semipalatinsk test site in Kazakhstan on Halloween, called "Joe 14" by US intelligence but was actually the 18th Soviet test. The Soviets did test all over Siberia, but before January 1955 the overwhelming majority of tests occurred in the Semipalatinsk test site. I think under a broad enough definition that might count as Siberia, and it's most likely that Anguirus didn't first appear from the ground in Semipalatinsk, I mean it's not like Godzilla was first seen on Bikini Atoll, so I actually think this retroactive real life info works for the film. Regardless, it took three months for Godzilla to be sighted, so no matter what Anguirus did not travel from Siberia to the middle of the Pacific Ocean in like a couple of weeks, Anguirus is the product of a 1954 test, at least. Just keep in mind that the concept of the USSR testing in 1950's Siberia is all assumed stuff on the part of the filmmakers and they don't have access to 2020's wikipedia, it was all classified and even the locattion of Siberia was a guess on their part. That it reality lines up with the film to any degree is pure coincidence.

二代目アンギラス • 2nd Generation Anguirus

Height: 60 meters
Length: 100 meters
Weight: 30,000 tons
Abilities: Spiked Carapace, Burrowing

History: A second Anguirus appeared on Solgell Island in 1971, where he became a close friend to Godzilla (II). Observation posts set up on the island recorded this Anguirus leaving after a strange alien tape was played, though Anguirus was repelled from landing by JSDF forces. He came back, this time accompanied by Godzilla, when the tapes started playing again, arriving to find and battle the space monsters King Ghidorah (1st) and Gigan (1st). Anguirus suffered a wound to the face, but ultimately the two Earth monsters prevailed. Late in that same year, aftershocks from an underground nuclear weapons test devastated Solgell Island, and opened a fissure into which Anguirus fell. Anguirus wouldn't emerge again until 1974, when it came to attack what it knew to be a fake Godzilla. However, Anguirus' jaw was broken in the battle and it retreated. Twenty years later, Anguirus was on the new Monsterland and fully healed, before the Kilaakian invasion. The Kilaakians controlled Anguirus and used him to defend their base in Izu from the JSDF. Once control was broken, Anguirus joined the other Earth monsters in defeating King Ghidorah once and for all.

Notes: For the 2nd generation Anguirus, no backstory is ever really given. We're first introduced to it's existence in DAM, and the next time we see it it's back in the present rather than the futuristic Honda utopia. What's more, because he's a pre-home video kinda movie, it doesn't treat the existance of Anguirus like something it needs to explain or justify. The film figures that the audience of mostly chilren already know who Anguirus is and remember from DAM that he's on Monster Island, and as far as anyone involved in the production was concerned that was the end of it. So all we know is that in-universe, this second Anguirus was a well known quantity by 1971, and it lived on what was called "Monster Island" at that time (probably Solgell Island, not Monsterland), which already had a form of surveillance established, albeit nothing on the scale of what's established by 1994. This would suggest this Anguirus has been around for at least a little bit, and has developed some kind of relationship with Godzilla, and given the monster first appeared in our universe in 1968, somewhere between there and 1970 sounds aboot right. So, if we assume this Anguirus is from the Pacific Ocean, which test between 1968-1970 is responsible for mutating it? The assumption with a Godzilla movie is probably that, if it's in the Pacific, it's the US's fault somehow. And that's fair, but here's a more interesting idea: you know who ELSE is a monster that's the product of a 1968 Pacific nuclear test? Yep, that's right, the original Zilla, and Zilla isn't the US's problem, that was France's doing. The obvious choice from that list is the Canopus test, conducted on August 24th, 1968 on the Fangataufa Atoll, which at 2.6 megatons is one of the handful of French test tied for the largest, and the only in that group during that time, as well as the first two-stage thermonuclear test. However, that can't be the same test responsible for Zilla because that occurred on the Moruroa Atoll. As far as I know, the specific test responsible for Zilla was never made explicit, but as Zilla doesn't appear in the Showa timeline at all, it's not really a connection worth making. Again, same thing applies here, although to a lesser degree. Nuclear tests are state secrets most of the time, especially in the 60's, so the filmmakers didn't have a specific test in mind, they just wanted another Anguirus. All things considered, though, blaming the Canopus test for the 2nd generation Anguirus fits into the Showa timeline even more nicely than blaming Joe 14 for the 1st generation one.
     It's also worth bringing attention to the fact that, just as in real life we had partial test ban treaty emerge as a response to the realities of continued testing, the Godzilla movies aren't happening in a vacuum either. We see alien technology be reverse engineered and we have humans on a Jovian moon before the end of the 60's, to say that history would have changed not at all with respect to nuclear testing in a world where Godzilla really exists would be absurd. So the bottom line is that ultimately we just can't know for sure where Anguirus came from. However, given that Megalon obviously references the real world news of underground testing from 1971, and the only difference with our world is the name of the island, we can assume that despite whatever affects the appearance of monsters had on the history of nuclear testing in-universe, it did at the very least continue happening. Therefore, it's not totally unreasonable to at least suggest that a similar-ish test occurred on one of France's Pacific testing sites between 1968-1970, and that's what I'm going to assume is the case.

アンギラス • Anguirus (Dream)

Height: 60 meters
Length: 100 meters
Weight: 30,000 tons
Abilities: Spiked Carapace, Burrowing

History: The movie monster Anguirus appeared in the young boy Ichiro Miki's dreams of Monster Island, presumably sharing the same background as the Anguirus from the films.

三代目アンギラス • 3rd Generation Anguirus

Height: 90 meters
Length: 160 meters
Weight: 60,000 tons
Abilities: Anguirus Ball, Spiked Carapace, Tail Club

History: Anguirus appeared sometime between 1997 and 1999 and formed a relationship of some kind with Godzilla (Final), though the details are unclear. In 2032, Anguirus was genetically modified by Xiliens to add M-base to its DNA, allowing them to be controlled telepathically and use it as a weapon against the Earthlings if need be. Anguirus was first deployed in Shanghai where they breifly engaged the EDF ship Karyu before being recalled by an Xilien UFO in a false display of assistance, making the Earthlings believe they were removing Anguirus. After new leadership took over, Anguirus was released back in Shanghai where it finally destroyed the Karyu. Once Godzilla was released, Anguirus was again deployed near Mt. Fuji along with Rodan (4th) and King Caesar (2nd) in an attempt to stop Godzilla. Godzilla won the battle, but spared Anguirus and the other monsters. It is unknown what became of Anguirus after the invasion was thwarted.

Notes: Boiler plate Final Wars disclaimer: the film had all explicit dialogue references to continuity cut. So, we don't know the details, and until somebody publishes one of the earlier drafts, we can't know. That said, we do know a little, and something the supplementary materials tell us is that the monsters aside from Kaiser Ghidorah are not new, and definitely DO have a history in-universe, and we should assume as the audience that those histories are familiar and similar to what we've already seen in previous films. As such, based on Godzilla sparring Anguirus, Rodan, and King Shisa in the final cut of the film (the scene depicting him blasting them was shot, but cut), we can assume that Godzilla has some sort of past relationshhip with them that's at least mildly positive. Authorial intent, then, would leave us to believe that this Anguirus is the same individual as the 2nd generation, the one from the Pacific that befriended Godzilla in the Showa timeline. On the surface this doesn't work because the damn thing has a club on it's tail, for starters, but also the size is off, it's way larger. The VS series told us that newer nuclear technology creates bigger monsters, so that's one way we could justify the 3rd generation Anguirus being bigger if it's meant to be the same individual. The other way is that the Xiliens tampering with its genes to add M-base caused it to mutate further, which, given it's literally genetic tampering, probably should have happened. Your mileage may vary here whether you think either of those is enough to change whatever the 2nd generation Anguirus looked like originally into what we see in Final Wars as opposed to what we see in DAM, but for me, I think the genetic manipulation by Xiliens is probably enough to turn on some weird atavistic genes in Anguirus and give them that gnarly tail club. Of course, we know that if this Anguirus did have a relationship with Godzilla, it must have happened after July 1996 but before the Antarctic winter of 1999, because that's the only time Godzilla could've met them. This means that whatever the case is, this Anguirus not only looks like at least a different species, but their history is so different by necessity that there's not a lot we can take to heart based on the "none of the monsters are new" paradigm. The end result for the audience is, of course, the same, but whether this Anguirus is the equivalent to the 1st, 2nd, or a totally unknown third Anguirus that just never appeared in the Showa timeline is impossible to say for sure. For authorial intent, though, I'd have to call it the same as the Pacific/2nd generation one. After all, that Anguirus was very chill, and it seems more reasonable that it could've remained unnoticed for thirty years. After all, if the Zilla of Final Wars is also the same as or the offspring of the individual from the GMK timeline, then we have a precedent set for French nuclear tests creating monsters in the late 60's that go undetected for 30 years. So, my hashtag film theory is that in the Showa timeline, the test responsible for the 2nd generation Anguirus happens on the Fangataufa Atoll and is parachonically analogous to the Canopus test, but in the GMK/VS-3 timeline, that test didn't happen, and instead both that same Anguillosaurus and the Amblyrhynchus that became the original Zilla were mutated due to a test on the Moruroa Atoll.

アンギラス • Anguirus (GMMG)

Height: 60 meters
Length: 100 meters
Weight: 30,000 tons
Abilities: Spiked Carapace, Burrowing

History: Another mutant monster of the atomic age, Anguirus appeared on the shore of Yokosuka in 1972 but was quickly repelled by a battalion of JXSDF forces, including Maser Cannons and Multipurpose Tanks.

Notes: The description of this event in the Completion book, which lists a number of such encounters in the history of the GMMG timeline, clearly is the same exact scene as Godzilla vs. Gigan. Another incident from that same year has Gigan appearing, so the implication here is that the events of that film still happened in the GMMG timeline with a couple of major differences, differences which answer to the names of "Godzilla" and "King Ghidorah." Without the 1st Generation King Ghidorah to use as part of their invasion plan, that might explain why it happens the year after the event's Showa continuity counterpart, and it also makes it a little easier to explain how the invasion was thwarted without Godzilla. Basically, if Anguirus showed up, that scene where the Earthlings play the action tape not understanding it probably still happened, causing Anguirus to go wild. This means that our core ensemble cast of Gigan is still snooping in the GMMG timeline, and would be able to take out the Nebulan's control center (which obviously wouldn't be Godzilla Tower in this timeline), leaving Gigan vulnerable. And without Ghidorah to back them up, well... we saw the Masers get some good hits in on Gigan in the original film, so it's not unreasonable to see how the Nebulan invasion could have been stopped under these circumstances.

アンギラスⅠ • Anguirus I

Height: 60 meters
Length: 100 meters
Weight: 30,000 tons
Abilities: Incandescent Light, Ultrasonic Roar, Spiked Carapace

History: After arising from the permafrost of Siberia, Anguirus made a bee-line for Beijing, where it attacked the city alongside Rodan I. The experimental Chinese bioweapon Hedorah was deployed, and successfully killed both monsters, but went out of control and went on a destruction spree of its own.

Notes: The prequel novelizations treat most of the monsters as being otherwise identical to their counterparts from the 1954 continuity family, and info from the theater program even tells us the original Kamacuras not only looks just like the Showa version, but is the same size as well. The major difference that's hard to explain, then, is the timing. Anguirus I is also from Siberia, just like the 1st generation Anguirus, but first appears 50 years later than in the Showa timeline. Is that because the testing happened later? Is Anguirus also part plant and had to take a few decades off to do some HGT shenanigans? We just don't know. I don't want to speculate too hard on this because personally I think this represents a discontinuity between the film and licensed material - the author of the novels was clearly being a turbo nerd while Gen Urobuchi was trying to do something very different. But, if we can have an HGT plant Godzilla, I don't see why we can't have the affects of nuclear testing be delayed for some time. After all, we kinda see that happen in the previous note about the 3rd generation Anguirus, so it's not too unreasonable to suggest that maybe something similar happens in the AniGoji timeline. In which case, Anguirus I is clearly the same individual as the Showa timeline's 1st generation Anguirus, and Anguirus IV is meant to be the same individual as the Showa timeline's 2nd generation Anguirus. Anguirus II, the one from South Africa, seems to be entirely new, and nothing at all is known of Anguirus III. If the GFW Anguirus isn't the Pacific individual after all, it may be the equivalent of the prequel novels' II or III.

アンギラスⅡ • Anguirus II

Height: 90 meters
Length: 160 meters
Weight: 60,000 tons
Abilities: Spiked Carapace, Burrowing

History: A second Anguirus appeared a year after the first, this time in South Africa.

Notes: The appearance of a Toho radiovore monster in South Africa is really interesting. South Africa is unique in that it is the only independent former nuclear power. It had a nuclear weapons program, and officially they got as far as selecting and preparing a test site in the late 70's before international pressure from the US and France caused them to shut it down, and by the end of the Cold War had dismantled every nuclear weapon they created. But, of course, this is fiction, so it's entirely possible that in the timeline of the novels things went a little differently and South Africa did go through with the tests in the Kalahari desert (which were underground tests), which went even worse than expected due to causing the creation of another Anguirus... y'know, thirty something years later. The other possibility is even more interesting, because it involves real life alternate history... kinda. So, you know the Vela Incident? If you don't, check out this fun little vaguely spooky video from Dark 5's second channel. If it was a nuclear test, the major suspects are either Israel, South Africa, or both countries working in collaboration with each other. It's location on Bouvet Island between South Africa and Antarctica is also interesting. Whatever the case is, the lore implication is too interesting to ignore, so if you ask me, in the AniGoji timeline, either South Africa continued its nuclear ambitions... or the Vela Incident really was connected to them.
     As for the stats used here, they are completely conjectural, but given what we learn from the VS timeline where the 3rd generation Godzilla - a product of nuclear material from the late 80's - is larger than the one created in the 50's, we should also expect that rule to follow for other radiovores. Therefore, if Anguirus II was created by the Vela Incident or an alternate universe Kalahari desert test, we're looking at the late 70's again, 1979 or so. Since the 3rd generation Godzilla's height is 1.6 times the original, applying that to the 1st & 2nd generation Anguirus gives us a height of 96 meters and a length of 160 meters. This is similar to the dimensions of the 3rd generation Anguirus, so for the sake of consistency I'm assuming those stats for Anguirus II. This could support the idea that the 3rd generation Anguirus is actually the same individual as Anguirus II, rather that 2nd/IV, but without more information it's just a guess.

アンギラスⅢ • Anguirus III

No Data

History: The existence of Anguirus II in 2006 and Anguirus IV in 2030 means that a third Anguirus appeared at some point between them, but nothing of it is known.

アンギラスⅣ • Anguirus IV

Height: 60 meters
Length: 100 meters
Weight: 30,000 tons
Abilities: Spiked Carapace, Burrowing

History: The fourth Anguirus was discovered in the Pacific Ocean, and made landfall in Los Angeles along with Baragon II, Varan II, and Godzilla (Earth), before being killed by Godzilla alongside the other monsters.