Nihilego attaches itself to the cranium of a host, causing abnormal behavior from them
Nihilego is an Ultra Beast that resembles a jellyfish. The bell is semi-translucent and encircled with several white, star-shaped markings. The wavy rim of the bell flares outward and is bright blue. Its tentacles appear gelatinous and give it a vaguely humanoid shape. Several tentacles mesh together forming the appearance of a cape or long hair, while four shorter tentacles resemble shorter hair and arms. Two long tentacles make up the legs of the human shape. In addition to its shape, it is sometimes seen acting like a young girl. According to its concept art, Nihilego's body is made of various types of glass.
Nihilego was the first Ultra Beast to be discovered by Mohn of Aether Foundation. Mohn was the one who conned Nihilego's name. Nihilego live in another world named Ultra Deep Sea. Although its exact levels of intelligence are unknown, it is believed to act upon a self-preservation instinct.[1]Wicke from the Aether Foundation describes Nihilego's capabilities as such:
Its most distinctive feature is its parasitic capability. When Nihilego latches on to a host, it does not manipulate its actions directly. Rather it awakens the host’s own capabilities and boosts them to an extreme extent in order to protect itself.
It injects the host with a sort of neurotoxin to achieve this effect. This neurotoxin of Nihilego’s is incredibly stimulating and inspires feelings of extreme excitement and a lack of inhibition in its host. In other words, anything or anyone that Nihilego latches on to will have its native skills forcibly activated to their fullest extent and will then act as it naturally desires to.
Wicke further claims that Nihilego, like all Ultra Beasts, stores an energy within its body similar to the aura seen around Totem Pokémon.[2] This energy is called Z-Power. In The Homecoming Crown!, Nihilego are capable of creating illusions and seeing the memories of humans. That same episode also showed that Nihilego can demonstrate emotions other than self-preservation and the ability to heal people.
Spoiler warning: this article may contain major plot or ending details.
As shown with Lusamine, Nihilego is capable of physically merging with a host. In this "merged" state, the bell loses its stars, developing several iridescent spots across its surface. The host's body is visible within the bell with their legs dangling beneath it. Its eight tentacles become long and flattened and have numerous deep black spots with various colored diamond-shapes inside. Four of the tentacles are connected to the bell via frilly white structures; these tentacles have four spines protruding from them that can be used similarly to hands. The remaining four tentacles each terminate in a single larger spine that, as depicted in 10,000,000 Reasons to Fight!, injects its toxins into the ground while sharp rocks grow below. While the same episode shows that Nihilego can willingly end this merger and it may be disrupted in other ways as well, the lingering toxins and the shock of the separation can leave the host in critical condition, both physically and psychologically.
The toxins produced by Nihilego may remain in the host's body, even after Nihilego has left their body. This can leave the former host to remain ill for unspecified amounts of time and treatment may be necessary. Nihilego leaving a host's body can also cause unconsciousness, as is the case with Lusamine, however it unknown whether or not this is because of Nihilego's toxins, the stress of fusion or the overwhelming amount of Z-Power within her body.
In The Homecoming Crown!, a Shiny Nihilego, nicknamedLillie, was revealed to have rescued Mohn after he had disappeared into an Ultra Wormhole and made him see it as Lillie after he developed amnesia. Once Mohn's memory of his real family was restored, Nihilego was invited into the family and caught by Gladion.
Other
Nihilego debuted in a flashback in A Masked Warning!, where Gladion revealed to Ash that Lillie was once attacked by one when she was younger, resulting in her present fear of touching Pokémon. It reappeared in a flashback in Mission: Total Recall! and The Homecoming Crown!.
Nihilego is inspired by jellyfish, with its body made of glass to contrast the soft bodies of real jellyfish.[3] It being Rock-type may be inspired by the fact that artificial glass is usually made out of sand. The specific species of jellyfish it is based on may be the Aurelia aurita or the Phyllorhiza punctata; the Ultra Beasts have been stated to be based on invasive species,[4] and the Phyllorhiza punctata is an invasive species in the waters surrounding Hawaii. It may also draw inspiration from Myxozoa, a class of microscopic parasites in the phylum Cnidaria (which includes jellyfish). In particular, the Myxobolus cerebralis is known to cause the infectious "whirling disease" in various fish species. The disease causes the fish to develop bone and neurological abnormalities that cause them to swim in a corkscrew-like "whirling" motion.
Nihilego may have also been inspired by Lillie and vice-versa. Throughout the games, Lillie mentions how her Ultra Beast-obsessed mother, Lusamine, chooses what clothes she wears and how she wears them, with both characters mentioning dress-up and outfits throughout the game. This implies that, in-universe, Lusamine has intentionally dressed her daughter up to resemble the Pokémon. Lillie's white sunhat resembles Nihilego's bell, with each of Nihilego's tentacles resembling Lillie's hair, legs, sundress, braids, and arms. Nihilego's white coloring with a blue accent is reminiscent of both of Lillie's outfits seen in the games. Furthermore, Nihilego's shiny coloration has a yellow hue, making it resemble Lillie's long blonde hair. Nihilego's Pokédex entry in Pokémon Moon states that "sometimes it can be observed behaving like a young girl." The anime episode The Homecoming Crown! notes the similarities between a shiny Nihilego and Lillie.
Name origin
Nihilego may be a combination of nihil (Latin for indefinite nothing) and ego (Latin for I), which together roughly translates to "I am nothing" or "I have nothing". Ego may also refer to the part of the psychic apparatus that governs rational decision-making, and together with nihil reflects how the creature may have no ego, and only have an id (the survival and instinctual part of the psyche). The former may reflect its victims' lack of will outside their focus on Nihilego, while the latter may represent Nihilego's role in dominating the desires of its victims.
Uturoid may be a combination of 虚ろ utsuro (void) and void. It might also involve asteroid or meteoroid, 鬱 utsu (depression), 移ろい utsuroi (transience), the suffix -oid (meaning "of similar form"), and id.
In other languages
Language
Title
Meaning
Japanese
ウツロイド Uturoid
From 虚ろ utsuro, asteroid, meteoroid, void, id, and possibly the suffix -oid (meaning "of similar form")
↑Wicke, Pokémon Sun and Moon:"When the UBs pass through the Ultra Wormhole, they are bathed in a great deal of this energy and likely store it within their bodies."