K9999

Key takeaways

K9999 belongs to biology; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect K9999 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of K9999 from memory before moving on to harder problems.

Reference excerpt

K9999 (pronounced Kay Four-Nine) is a fictional character from SNK's fighting games The King of Fighters. He is a hotheaded, psychopathic member of the NESTS organization who debuted in The King of Fighters 2001. He would later be re-introduced in The King of Fighters XV as Krohnen McDougall (クローネン・マクドガル, Kurōnen Makudogaru). The 9999th clone of Kyo Kusanagi, he has pyrokinetic abilities and is able to transform his arm into a long-deformed flesh tentacle. He has an intense hatred towards K' and despises everyone around him. Despite this, he considers Ángel as a friend. In KOF XV, he returns as the leader of Team Krohnen alongside Kula Diamond and Ángel. K9999 is heavily based on Tetsuo Shima, a character from Katsuhiro Otomo's manga Akira. Due to copyright issues, K9999 was removed from The King of Fighters 2002: Unlimited Match in 2009; he was replaced by a new character called Nameless. After twenty years of his absence, K9999 was added to The King of Fighters XV with a major redesign as claimed by artist Eisuke Ogura. He was originally voiced by Nozomu Sasaki who was replaced by Kenn. In the story, K9999 written to be the inferior rival of the NESTS arc protagonist K' as the writer Akihiko Ureshino claimed the staff wanted to a different take from Kyo and Iori Yagami from the Orochi arc who see each other as equals. Critical response to K9999 was initially positive but the removal from several games led to theories about the company committing several copyright violations, making it impossible for him to return. With KOF XV there were initially multiple theories about Krohnen's identity based on his similarities with K9999 until the release of the game which confirmed they are the same character but under a different name. Krohen earned a favorable response too based on his design and gameplay despite still being like the original.

Appearances K9999 was first introduced in The King of Fighters 2001 as the last experiment the terrorist organization NESTS made based on the fighter Kyo Kusanagi. During the new tournament held by NESTS, the organization starts falling apart after the death of agent Zero. The NESTS team with Ángel and K9999 attack their allies Kula Diamond and Foxy, but depending on the characters used, the rebellious K' interrupts them. Following Igniz' suicide, K9999 and Angel leave the organization. The two characters return in The King of Fighters 2002 as part of another NESTS team but the game offers no narrative. In The King of Fighters XV, he goes by the name Krohnen McDougall and alongside Angel, he kidnaps Kula to have exchange of money. In the aftermath, they return Kula to her caretakers but still decide to continue travelling the two together with Angel telling Krohnen he is still the old K9999. His role in The King of Fighters 2001 is also retold in Akihiko Ureshino's two novelizations based on the game.

Conception and development K9999 was based on Tetsuo from Katsuhiro Otomo's work Akira. In remembering the character, developers from SNK said that K9999 was a character they found difficult to talk about based on his controversial origins. While acknowledging the character had become popular in China and Korea, they had poor faith in addressing him again in the future in The King of Fighters series. Writer Akihiko Ureshino said K9999 is a bundle of homages—appearance, voice acting, and presentation—that seems dangerous to mention. While this tends to be the focus, his position was more of a stepping stone for NESTS arc protagonist K' than a rival. This is probably because, according to the setting, K9999 was assigned this clown role by his superior Igniz. K9999 was written to hate being K' who only seems as a troublesome person. He contrasted this inferiority complex with the more famous SNK rivalry between Kyo Kusanagi and Iori Yagami started in the Orochi arc as they instead see each other as equals. The handling of this state constantly irritates K9999 in a distorted way, but ultimately, this was all part of Ignis's test on K'. K9999 didn't appear on the main stage at all until his reappearance as Kronen in The King of Fighters XV but K' probably didn't feel anything about it as reflected on their rival intro. K9999, who was supposedly created as a clone in the NESTS lab, should have no connection to K' whatsoever. Nevertheless, the reason K9999 is so conscious of K' is because the people at NESTS value K', who is supposed to be a traitor, more highly than K9999, who is an imperfect clone soldier. Ureshino took into acount this when writing his novelizations based on the games. In 2016, Yasuyuki Oda said that SNK might reexplore K9999 and Angel again as it had been several years after their last appearance. When discussing the release of the character in The King of Fighters XV Eisuke Ogura said that Krohnen is really a former NESTS experiment who had his hair grown up and had his body replaced with an armor and a glove to. Ogura wanted Kronhen to look powerful in his new design.

… excerpt ends here. Continue reading the full article.

Worked examples

Example 1 — a first encounter with K9999

Start with the simplest possible case. Write down what K9999 claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to K9999 before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about K9999 ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of K9999

In research: K9999 appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses K9999 in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: K9999 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Fictional characters with fire or heat abilities, Genetically engineered characters in video games, Male characters in video games, so understanding it makes those chapters shorter.
In everyday life: Look for K9999 outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study K9999 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what K9999 means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain K9999 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is K9999 in simple terms?

K9999 (pronounced Kay Four-Nine) is a fictional character from SNK's fighting games The King of Fighters. He is a hotheaded, psychopathic member of the NESTS organization who debuted in The King of Fighters 2001.

Why does K9999 matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study K9999?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on K9999.