Perhaps you've already encountered these logically absurd creatures across various video platforms: a three-legged shark wearing blue Nike shoes featured as a new income-generating project for farmers in wealth-building programs; monkeys growing from giant bananas and giraffes wearing astronaut helmets becoming protagonists in passionate anime music videos from Bilibili content creator @咪克菌; or pointed-headed fish-human hybrids stepping on nail-studded boots from social media ads, transforming into the next generation of internet influencers from Bilibili creator @詭仙人在此.

In the Chinese internet sphere, these are typically called "Foreign Shan Hai Jing" or "AI Shan Hai Jing," while overseas, they're labeled as "Brain Rot." In 2024, "Brain Rot" became Oxford Dictionary's word of the year. This term carries negative connotations, defined as "mental and intellectual deterioration caused by excessive consumption of low-quality social media content" - essentially "becoming mentally numb from scrolling."

However, this doesn't deter enthusiasts from continuing their obsession. Rather, the "Brain Rot" label makes it easier for them to find this type of content. The "Brain Rot" phenomenon extends beyond just videos. Related imagery from "AI Shan Hai Jing" has been transformed into various toys with impressive sales on e-commerce platforms. Entering "Brain Rot" into Steam immediately brings up dozens of games.

These games mostly feature "Brain Rot" in their titles and include related meme creatures - some original, others referencing popular internet favorites - but all clearly AI-generated in appearance. The gameplay varies significantly.

What kind of people create such games, and beyond making money, what else motivates them? We interviewed developer Matías from Chile, originally a 3D modeler who created the most successful "Brain Rot" themed game to date.

Matías's game is called "THE LAST TRAIN: Baquedano." This is a PS2-style first-person psychological horror game where players assume the role of a worker who accidentally falls asleep on the subway, waking up at an unfamiliar terminal station. They must search for clues, avoid "mysterious entities pursuing them," and escape - predictably, these mysterious entities are the AI Shan Hai Jing composite creatures.

Looking purely at numbers, "The Last Train" achieved an 89% positive rating on Steam with several thousand sales - seemingly unremarkable and barely creating ripples on Steam. However, it's actually one of the most successful Brain Rot themed games on the platform. "The Last Train" leads 99% of Brain Rot games in both reputation and sales, maintaining this position even when expanding to itch.io and Nintendo eShop.

Most AI Shan Hai Jing games either have few reviews or positive ratings around 60%, clearly showing their rushed production and "riding the trend and running" nature. Matías explained that "The Last Train" originated from a Game Jam prototype. Players enjoyed the prototype, so he expanded it into a complete game. Before release, he never imagined it would gain such support, considering himself an inexperienced developer who only achieved "decent" results.

The game's success largely benefits from peer comparison. The mediocre state of AI Shan Hai Jing games mirrors the spread of Brain Rot memes themselves. Before having visible imagery, Brain Rot culture's popularity emerged alongside numerous subculture elements, profanity, and crude humor. Its essence involves stacking and combining bizarre materials, like "Brain Platinum" advertisements, using repetitive content to attract attention and create lasting impressions.

This remained true even when the first AI Shan Hai Jing image emerged. In January 2025, when a shark wearing three Nike shoes appeared as the first "divine beast," it was immediately followed by a string of Italian profanity involving religious insults. "Tralalelo tralala" - even as you read this article, countless AI divine beasts are being continuously created. Simply feeding AI a few words generates a unique beast, embedding personal agendas or materializing supposedly unique ideas.

Some might question whether this constitutes creation, but for many, watching these indescribable beings emerge under their influence provides endless entertainment. Matías said his decision to create such a game wasn't because the meme was popular, but because he noticed the people behind it.

Matías first encountered the AI Shan Hai Jing shark character, but his favorite became "Tong Ge" - the mysterious entity pursuing the protagonist in "The Last Train." Tong Ge's scientific name is "TungTungTungSahur," a stick-wielding figure. This name combines the onomatopoeia of stick-hitting sounds with Indonesian for "pre-dawn meal," carrying little meaning but sufficient magical awkwardness - a naming principle for most AI Shan Hai Jing creatures: meaningless but brain-washing and ear-worming.

Just from this name, AI Shan Hai Jing enthusiasts created extensive lore for Tong Ge. For instance, when hitting people, Tong Ge unconsciously makes "tung tung tung" sounds; while its scientific name is "TungTungTungSahur," the more "Tung"s you pronounce, the harder it hits. As more awkwardly-named divine beasts emerged, netizens developed various activities: identifying creatures by their awkward names from images, "finding spelling errors in divine beast names," or pairing creatures as archenemies.

They approach these like exam questions, taking pride in beast familiarity and even hosting related competitions. Additionally, divine beast fans create artwork and animations like devoted followers; in virtually every comment section, people seriously discuss beast combat abilities and gameplay as if an actual "AI Shan Hai Jing" game existed.

When Matías first encountered these AI images and awkward names, he, like most people, thought "this is pure nonsense, stupid characters with stupid names" - completely accurate, as AI Shan Hai Jing's audience indeed includes many teenagers under 15, with much content emerging from their bored daily lives. This explains why many AI Shan Hai Jing activities resemble test questions.

After understanding AI Shan Hai Jing's essence of seeking entertainment from daily life, Matías decided to create a themed game. His "The Last Train" also roots itself in daily life, seeking experiences beyond mundane existence, but he wanted to excavate daily horror.

The game's full title includes "Baquedano," referring to Baquedano Plaza, an important landmark and major subway station in Chile's capital Santiago - essentially their "People's Square Station." This location represents one of locals' most frequent destinations and common activities. This similarity connects "The Last Train" with 2023's hit game "Exit 8" - both attempt building horror upon the ordinary.

Matías describes it as "a psychological horror game combining local urban experience, popular culture, and simple extremes to awaken Latin American collective imagination." Despite his sophisticated description, it essentially helps more Chileans recall their daily subway commutes, with things emerging from daily cracks being closest to audiences and easier to resonate with.

For Matías, AI Shan Hai Jing represented ready-made popular material with topics, popularity, recognition, and most importantly - no cost. Matías doesn't deny his game's "trend-riding" component. He clearly understood from the start that he needed a memorable enemy for "The Last Train," "wanting something with viral potential, and Brain Rot characters were perfect choices, recognizable in the best, weirdest way."

Brain Rot's popularity partly stems from these AI-synthesized creations transcending language and cultural barriers. Before creating this game, Matías was a 3D artist continuously seeking this quality. Throughout his creative career, he received comprehensive artistic enlightenment from his filmmaker father, then systematically learned writing, sound design, and 3D design. These skills enabled him to transform concepts into reality and accumulated the foundation for single-person game development.

However, his works remained lukewarm throughout this process. Until he first encountered AI Shan Hai Jing videos on TikTok in April, seeing a rare public IP with visual imagery. Many people recognized AI Shan Hai Jing's commercial potential as it exploded. Related products spread from online content to offline merchandise, quickly establishing complete product chains including badges, emoji packages, and dolls, with TCG card brands emerging and related toys appearing in domestic supermarkets.

In Matías's view, creating an outstanding story today might be expensive, but one can "ride trends" to get "as close to outstanding as possible." More importantly, he saw his desired expression in these bizarre divine beasts: "People are enjoying its essence - a weird but interesting moment. Some might create stories or games around it (like we did), it's not something with lasting cultural impact, more like a shared joke."

Some compare the AI Shan Hai Jing community with the SCP community. Both are collaborative creations, but AI Shan Hai Jing lacks systematic structure - nobody regulates whether your new divine beast conforms to rules or has proper Italian naming, maintaining wild growth. This means everyone can make their expression or "personal agenda" part of this system.

Before the AI Shan Hai Jing joke becomes outdated, it leaves a platform for creators like Matías to contribute something personal, like an explosion. Giving meaning to meaningless shells motivates their AI Shan Hai Jing derivative creations. Nobody witnessed the Big Bang, but its afterglow left us an entire universe to explore - videos, illustrations, and games work similarly.

After "The Last Train's" success, Matías decided to formally enter the gaming industry as an independent developer targeting commercial games. Despite this game's limited success - this marked my first encounter with a game celebrating surpassing the "1000 sales milestone" - it doesn't diminish his gaming commitment. He recently traveled far to exhibit "The Last Train" at the Bitsummit independent game show in Kyoto.

When discussing AI Shan Hai Jing's significance to him, Matías initially elaborates on his game's intended expression: "It gave me an opportunity to blend daily observations with desires to transform viral phenomena or urban legends into interactive stories full of suspense, nostalgia, and social criticism..." But he immediately adds: "But none of this matters."

Brain Rot's popularity stems from its mindlessness. When people constantly try attributing meaning to everything, they crave simple feeling and pure laughter. We pursue meaning, but life is already too complex - sometimes being empty-headed like AI Shan Hai Jing works fine too.