【Kaiju No. 8】 Kaiju No. 1 is the Oldest Kaiju! Explaining Its Strength, Abilities, and the First User of the Numbers


Let’s feature Japan’s oldest giant Kaiju, “Kaiju No. 1”! Kaiju No. 1 is a character in the manga “Kaiju No. 8”, which is a major hit on “Shonen Jump+” alongside “SPY×FAMILY”. This Kaiju has now become a legendary being. In this work, a unit called “Fortitude” is used to measure the strength of Kaiju. What would be the Fortitude value of Kaiju No. 1? We will delve into the details of Kaiju No. 1’s strength, abilities, and the user of the Number 1.

What is Kaiju No. 8?

Let’s feature “Kaiju No. 1”, the oldest identified Kaiju from the characters of “Kaiju No. 8”, a manga considered as one of the biggest hits on “Shonen Jump+” along with “SPY×FAMILY”. We will delve into details about the strength, abilities, and the first user of Kaiju No. 1, but first, let’s provide some information about “Kaiju No. 8”. We will start with an overview of “Kaiju No. 8”, followed by a brief synopsis.

Overview of Kaiju No. 8

“Kaiju No. 8” is a Japanese SF battle manga by Naoya Matsumoto, set in Japan, a country with one of the highest rates of Kaiju appearances in the world. It has been serialized on Shueisha’s web comic distribution site “Shonen Jump+” since July 3, 2020. Since its serialization, the manga has exploded in popularity and, as of December 2023, has exceeded 12 million copies in cumulative domestic circulation.

On the other hand, while the “Shonen Jump+” site usually updates its works every Friday, the update schedule for “Kaiju No. 8” changed from August 28, 2020, in line with the author’s intention to update at a pace of “drawing three chapters and then taking a break”. Interestingly, on the days when there is no new chapter, an illustration collection called “Kaiju Hyakkei” featuring everyday scenes with Kaiju is published.

“Shonen Jump+” has been particularly popular since 2016 for its original works, continuously producing hit after hit. Amidst this, “Kaiju No. 8”, the third serialized work of manga artist Naoya Matsumoto, grew to rival “SPY×FAMILY” by March 2021, becoming one of the biggest hits on “Shonen Jump+”.

Interestingly, the Kaiju in “Kaiju No. 8” are numbered like typhoons, and their strength is measured in a unit called “Fortitude”. This is said to implicitly indicate that the Kaiju are symbols of natural disasters. Unlike the special effects monster movies like “Godzilla”, which symbolized air raids during World War II, “Kaiju No. 8” is part of the lineage of Kaiju works released after the 2011 Great East Japan Earthquake, represented by movies like “Shin Godzilla” from 2016.

Synopsis of Kaiju No. 8

The protagonist, Kafka Hibino, vows with his childhood friend, Mina Ashiro, to exterminate all Kaiju after his hometown is destroyed by them in his childhood. However, this dream fades away, and at 32 years old, he works as a Monster Sweeper, dismantling the corpses of Kaiju. Later, after learning about the lifting of the age limit for the Defense Corps, he decides to enlist but is suddenly assimilated by a mysterious organism and transformed into “Kaiju No. 8”.

Kaiju No. 1 is the Oldest Kaiju! But Who Defeated It?

Kaiju No. 1 – The Oldest Kaiju

Now, let’s shift our focus to the main theme of this article: Kaiju No. 1, a character in “Kaiju No. 8”. First off, let’s discuss Kaiju No. 1’s profile. Kaiju No. 1 is considered the oldest identified Kaiju, but little is known about its origin. In “Kaiju No. 8”, it is shown that the head of the Japan Defense Corps, Gonshi Shinomiya, has some information, but other details remain shrouded in mystery.

This Kaiju had already been defeated at the start of the series, and its remains were being used by the First Division of the Defense Corps, led by Gen Narumi. Given that Kaiju No. 2 was defeated in 1972, it’s certain that Kaiju No. 1 existed before that. This implies that it appeared and was defeated a long time ago. Moreover, records indicate that Kaiju No. 1 was a fearsome being capable of foreseeing the future and launching unavoidable attacks.

Identification numbers are codes assigned to giant Kaiju, given in the order of their appearance. Once defeated, Kaiju are examined and experimented on by the Defense Corps and can also be weaponized. These weaponized Kaiju are known as “Numbers” and are used by Defense Corps members in combat.

Who Defeated Kaiju No. 1?

Kaiju No. 1 appeared and was defeated long before Kaiju No. 2, but who exactly defeated it? Although Kaiju No. 1 was defeated much earlier than Kaiju No. 2, which was defeated in 1972, the identity of its defeater remains unknown.

No information about the defeater of this Kaiju has been revealed. Currently, Kaiju No. 1 is used as a weaponized Kaiju, “Number 1,” by Gen Narumi, the captain of the First Division of the Defense Corps. When using Kaiju No. 1, a cross-like pattern appears in Narumi’s eyes. Narumi has built his top-notch record in the Defense Corps by utilizing Number 1’s precognitive abilities.

The Strength and Abilities of Kaiju No. 1

The Ability of Kaiju No. 1: Precognition

According to the Defense Corps’ reports, Kaiju No. 1 possesses the ability to foresee the future and inflict unavoidable attacks on its enemies. This results in enemies receiving unexpectedly sudden attacks. The mechanism of this precognition involves visually capturing signals emitted from the brain when a living creature moves, allowing the detection of information before the enemy’s body actually moves.

By using precognition, it becomes possible to anticipate an opponent’s moves and launch inescapable attacks. This ability was utilized by Gen Narumi as Number 1. Naturally, it is believed that Kaiju No. 1 possessed this ability, and considering its immense power, it raises curiosity about who managed to defeat it.

The Strength and Fortitude of Kaiju No. 1

The first giant Kaiju in Japan is Kaiju No. 1, the first to be given a codename. In the manga “Kaiju No. 8”, the Commander of the Defense Corps assigns these codenames to particularly powerful or difficult-to-defeat Kaiju. Since codenames are assigned in order, Kaiju No. 1 is the first discovered challenging entity. Additionally, the fate of Kaiju No. 1 is considered sealed, as it was already defeated by the Defense Corps.

A Kaiju is referred to as a “giant Kaiju” if its Fortitude exceeds 8.0. “Fortitude” is a scale indicating the strength of a Kaiju, where a higher number denotes greater power. Kaiju in “Kaiju No. 8” are classified based on this Fortitude scale, and those with a Fortitude above 8.0 are categorized as “giant Kaiju”, requiring multiple captains for subjugation.

Kaiju are divided into three categories based on their Fortitude: “giant Kaiju”, “main Kaiju”, and “minor Kaiju”. Giant Kaiju, with a Fortitude of over 8.0, are challenging individuals that require cooperation from multiple captains and are individually numbered. Next, “main Kaiju” have a Fortitude of over 6.0 and can be defeated by a single captain. On the other hand, “minor Kaiju” have a Fortitude below 6.0 and can be defeated by the squad members.

Generally, Kaiju are divided into two categories: “main Kaiju” and “minor Kaiju”. However, occasionally, a “giant Kaiju” with a Fortitude exceeding 8.0 appears. In “Kaiju No. 8”, 15 Kaiju have been classified as “giant Kaiju” so far. Notably, the protagonist Kafka Hibino’s transformation into Kaiju No. 8 has a Fortitude of 9.8.

The User of Number 1

What are the Numbers?

The Numbers (or Identified Kaiju Weapons) are weaponized versions of Kaiju with codenames. These are weapons that only a select few in the Defense Corps, such as captains and vice-captains, can use. Kaiju No. 1 has already been defeated and is now operational as “Number 1”, also known as “RT-0001”.

Number 1 was primarily developed based on the eyes of Kaiju No. 1. Not only was Kaiju No. 1 the first to be given a codename, but it is also known as Japan’s oldest Number and the first giant Kaiju to be introduced as a weapon.

The User of Number 1 – Gen Narumi

The one entrusted with operating Number 1 is Gen Narumi, the leader of the First Division. He is a young member touted as the strongest warrior in Japan against Kaiju. Normally stationed in the captain’s room, he lives a disorganized life, with his room cluttered with games and plastic models, reflecting his typical otaku hobbies.

He is also known to beg subordinates for money due to overspending on online shopping. Narumi self-praises his achievements on social media and shows envy when Mina’s achievements are highlighted. Despite notable shortcomings in terms of dignity, his capabilities as a captain are genuine, with his overwhelming results on the battlefield overshadowing all flaws. In missions, he shows a ruthless side, demanding only results and prowess from his subordinates.

In combat, Narumi wields a bayonet-type special weapon, “GS-3305”, and his eyes are embedded with an Identified Kaiju Weapon created from the retina of Kaiju No. 1. This device visualizes signals from a living creature’s brain, enabling the ability to predict movements, essentially a form of precognition. Although he already owns a specialized bayonet, Narumi possesses several weapons specifically for Number 1. Notably, the retina-based Number 1 is a contact-style weapon used on the eyes.

The Numbers are developed to inherit abilities from the original Kaiju. Thus, Number 1 inherited the precognitive ability of Kaiju No. 1, allowing the user to foresee the future in a similar manner. This ability works by reading the electrical signals inside the opponent’s body, predicting their movements.

However, these signals correspond to the brain’s “intentions” and are ineffective against inanimate objects or fully automated entities. It had a weakness in predicting movements of non-living or automated objects using precognition.

Yet, Narumi overcame this limitation with his extraordinary abilities. He can now predict movements of non-living objects, effectively completing the “precognition” capability. Not limited to electrical signals, he can comprehend everything from full-body sensors, temperature changes, terrain, and more, predicting upcoming events. With this precognition, Narumi defeated the formidable Kaiju No. 11.

Summary of Kaiju No. 1

In this article titled “Kaiju No. 1 in ‘Kaiju No. 8’ is the Oldest Kaiju!”, we have discussed its strength, abilities, and the user of Number 1.

In the manga “Kaiju No. 8”, the strength of Kaiju is measured using a unit called “Fortitude”. If the Fortitude is above 6.0, the Kaiju is considered especially difficult to defeat and is called a “giant Kaiju”, becoming a subject of special management. Interestingly, the Fortitude value of Kaiju No. 1 has not been revealed. However, being the first-ever giant Kaiju, it’s certain that its Fortitude is above 6.0.

Kaiju No. 1 also possessed the ability of precognition, which involves foreseeing the future to launch unavoidable attacks on enemies. Although Kaiju No. 1 has been defeated, it is currently used in combat by Gen Narumi, the leader of the First Division, as the weapon Number 1. Despite his disorganized personal life, Narumi has made remarkable achievements on the battlefield, expertly utilizing this weapon and the special bayonet-type weapon “GS-3305”.

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