Ultraman Arc — The Biology of Shagong

Ultraman Arc — The Biology of Shagong

Ultraman Arc Episode 1, “Arc to the Future”, aired on July 7th, JST, and within the bounds of a half-hour, we were introduced to a new world, with new heroes, including the Scientific Kaiju Investigation and Prevention center, or SKIP, and their young member Yuma Hize, as well as the mysterious giant whose power he wields, Ultraman Arc.

It also introduced us to Shagong, the angriest turtle!

Shagong is fascinating in the context of Arc — While being the first- well, actually it isn’t the first, but we’ll talk about Digelos later — the first Kaiju we get a full fight scene of, its biological niche is very different than the one it is presented in.

In nature, Shagong is a much smaller creature, a relatively common carnivorous Kaiju native to Japan. Traditionally subterranean in its habitat, Shagong are a species that SKIP is accustomed to.

That is, until the Oo-ze get involved.


Little is known about the Oo-ze, even in-universe. It’s not until Shu Ishido from the GDF successfully identifies it that it can be recognized. An Extraterrestrial Parasitic Organism, an Oo-ze breaks free from its stasis within the horn of the long-defeated Monogelos that acts as a landmark for Hoshimoto City, and latches on to a Shagong slumbering in a cave system.

And that Shagong, spurred on by the alien impulses of its new parasitic master, changes its diet from meat to calcium carbonate — a common compound used in all sorts of industries, including as part of limestone in building — and, when it begins to feed, makes that sucker grow. Soon, the Shagong goes from 5 meters tall, its natural height, to 54 meters, its body swollen with delicious, chalky calcium carbonate, as well as Oo-ze spawn gestating within, which begin to spill out as they suck the calcium carbonate from the Shagong’s digestive system.

Shagong’s natural powers, like an acid spit used to help melt cave walls for its nest, are turned into powerful weapons that threaten to melt down and destroy Hoshimoto, all to feed the Kaiju’s new hunger. Thankfully, its rampage does not last long — the hero Ultraman Arc appears, dispatching the mutated beast in almost exactly three minutes. From its corpse, the original Oo-ze, now nearly as large as the poor creature it was effectively puppeting, emerges, but it too is cut down, this time by a single slash of Arc’s blade.


It’s perfectly likely we’ll see other Shagongs again — albeit, perhaps not at the tremendous size of this mutant specimen. However, the Monogelos that the Oo-ze emerged from has been dead for 16 years — who can say if there aren’t more mutagenic parasites, ready to grow the next Shagong we see to similar sizes?

The only way to know any of this for sure is to watch Ultraman Arc as it airs — May we suggest doing so on our new English-language Youtube channel?