A developer added a cheat to Gradius to help him test it. He forgot to remove it. The Konami Code is still famous.
Kazuhisa Hashimoto was a programmer at Konami working on the Famicom port of Gradius. The arcade original required technical execution that made it difficult to test effectively — the game was fast, the ship died in one hit, and restarting repeatedly made systematic testing impractical. Hashimoto programmed a cheat into the Famicom version: Up, Up, Down, Down, Left, Right, Left, Right, B, A. Entering the sequence on the title screen gave the player every power-up immediately. He used it to reach deeper sections of the game efficiently. He did not remove it before the game shipped. Players discovered it. It became the most famous cheat code in video game history — later called the Konami Code — and Konami reused it deliberately across dozens of subsequent titles, first as an internal reference and eventually as a brand signature. Games, films, and websites have encoded it into their software as an Easter egg for decades after the fact. The code appears in products that have nothing to do with Konami. The Options system in Gradius — small drone copies of the player's ship that trace its exact flight path, doubling and tripling firepower at the cost of making errors more consequential — was also a significant design innovation. But it was the forgotten test input that defined the game's legacy. Hashimoto died in 2020. At the time of his death, the Konami Code was more than thirty years old and had appeared in hundreds of games, films, and cultural references worldwide.
After powering up enough of these to test them, my ears started stopping before my hands did. Gradius sounds good. The arcade version especially.
The Famicom port does its own quiet work. At the start of each stage's music, it briefly silences every sound effect so you hear only the three channels playing. With so little to work with, the way to make something heard was to take other things away.
And the arcade sound carries a story. It is said that a note crept into the bass line of the first stage that was never in the score — the composer, Miki Higashino, had written it correctly, and it was entered wrong. By the time anyone noticed it was too late, so it shipped that way. Later ports corrected it. Which means the music I have admired all these years carries a mistake nobody could take back.
People remember the version that stayed broken, not the one that got fixed. That may be why collectors still hunt for the board.
About this game
Gradius (1986) arrived on the Famicom as a port of Konami's 1985 arcade hit — and brought with it something no other Famicom game had yet offered: a power-up selection bar that let players choose how to develop their ship. Speed, missiles, double cannon, laser, Options (orbiting attack drones) — each run through Gradius is a strategic choice about which capabilities to prioritise. It is also the game that accidentally contained one of the most famous secrets in gaming history: a programmer's debug shortcut, left in the shipped code. Up, Up, Down, Down, Left, Right, Left, Right, B, A. A cheat code that should have been removed became a cultural landmark.
Key Features
Horizontal scrolling shooter with the Vic Viper spaceship navigating through enemy territory. Power-up capsule collection system: collect capsules to advance a selection bar, then choose from Speed, Missile, Double, Laser, Option, or Shield. The Option drones — spheres that mirror the player's position and fire simultaneously — are a defining mechanic of the series. Multiple distinct stage themes: volcanic planet, artificial fortress, volcanic cavern, moai heads, and more. Boss encounters at stage ends. The famous Konami Code cheat: Up, Up, Down, Down, Left, Right, Left, Right, B, A — grants full power-ups and was originally a debug tool.
Gallery
The Story Behind
The original Gradius was released in Japanese arcades in 1985 by Konami. The Famicom port followed on April 25, 1986 — among the earliest Konami games on the platform. The NES version launched in North America on December 26, 1986, making it one of the first NES games Konami released in the region. Kazuhisa Hashimoto, who was developing the home port, found the game too difficult to test repeatedly and created an input sequence to give himself full power-ups. He forgot to remove it before shipping. Players discovered it, shared it, and it spread — becoming known as the Konami Code. It was later included in Contra (1987), where it gave players thirty extra lives, cementing it in gaming culture permanently.
Tricks & Tales
The Konami Code — Up, Up, Down, Down, Left, Right, Left, Right, B, A — was created by accident. Kazuhisa Hashimoto, the developer of the Famicom port, created it as a personal testing shortcut and forgot to remove it before shipping. It was later included in Contra (NES, 1987), where it granted thirty lives, and became globally recognised as the most famous cheat code in video game history. The "Option" drones — the orbiting attack ships that follow the player's trajectory — defined a template that later shoot-em-ups would imitate for decades. Gradius (1985) predates R-Type by two years; the Option is the original, not the imitator. The moai head stage (Easter Island stone heads) became one of the most iconic recurring stage designs in shooter history.
Collector's Guide
Region & Compatibility
The Japanese Famicom version and the North American NES version are functionally the same game, with title unchanged between regions (one of the few Konami NES games to keep its Japanese name). The NES version was Konami's first NES release in North America. Famicom cartridge requires 60-to-72-pin adapter for NES play.
Maintenance Tips
Standard Famicom cartridge edge connector cleaning: isopropyl alcohol (90%+) on a cotton swab, allow to dry fully before insertion. Gradius has no battery save — it is a single-session game, making live gameplay testing practical. Controller A and B buttons require reliable response for the Konami Code and rapid fire sections. NES CIB with original manual is collectible and commands a premium.
Going deeper
Explore the machine this game ran on, and what to check before you buy or care for one:
What to Watch Out For
Before buying, these are the points worth knowing — from someone who handles original Japanese Gradius copies regularly.
Will this Japanese Famicom cartridge work on a North American Nintendo Entertainment System (NES)?
No, not without an adapter. The Famicom uses a 60-pin edge connector while the NES uses a 72-pin connector with a physically different form factor — the two are incompatible at the cartridge slot level. Third-party adapters exist that bridge the pin difference and allow Famicom cartridges to run in a NES. On a Japanese Famicom, NES cartridges face the same incompatibility in reverse. To play Japanese Famicom software, you need a Japanese Famicom, a Famicom-compatible clone console, or a NES fitted with an appropriate adapter.
How should I clean a Famicom cartridge to ensure reliable play?
Apply 90% or higher isopropyl alcohol to a cotton swab and gently wipe the gold-plated PCB edge contacts on the base of the cartridge. Never blow into the cartridge — breath moisture accelerates contact corrosion over time. If cleaning is needed inside, Famicom cartridges use 3.8mm security game bit screws (not standard Phillips); a security bit screwdriver is required to open the shell without damage. Note that most Famicom boot failures originate in the 60-pin console slot rather than the cartridge itself — cleaning the console slot contacts separately with a contact cleaning tool is often the more effective fix.
Before You Buy
Things worth knowing before you buy Gradius
A short checklist for buying a used Famicom cartridge wisely — useful with any seller, anywhere.
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Choose a seller who tests it before shipping
A copy that has actually been powered on and checked is a known quantity. An untested one is a gamble you only settle after it arrives.
Look for a seller who states it was function-tested and says what they confirmed. A serious seller can tell you exactly what was checked.
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Make sure it fits your console
This is a Japanese Famicom cartridge with a 60-pin connector; a North American NES uses a 72-pin slot, so it will not fit directly.
Play it on a matching Japanese console or a region-free system, and confirm the listing states the region.
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If this title saves your progress, check the battery
Cartridges that save use a small coin-cell battery that fades over decades — a dead one wipes your save without warning.
Ask the seller whether the save function was tested. Replacing the battery is possible, but doing so erases any existing save.
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Check that the contacts are clean
Dirty edge contacts are the most common cause of startup and sound trouble in cartridges of this age.
Choose a seller who cleans the contacts before shipping. A note that it was tested and cleaned means the basics were handled.
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Confirm it is genuine, not a reproduction
Sought-after titles are targets for reproduction boards with replacement labels.
Ask for a photo of the circuit board and look for factory markings. Favour a shop with a licensed second-hand dealer permit (古物商) — by law its stock has a traceable origin, your simplest guard against fakes.
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Read the seller's reviews and return policy
A 100% positive record across thousands of sales is close to a guarantee — packing, communication and problem-solving all work for everyone. A return policy protects you if something is off.
Read the feedback and confirm a clear return window before you buy.
The last step before buying anywhere is knowing what it's worth.
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Rooms this game lives in
Wander deeper — explore the themed rooms where Gradius sits alongside its kin.
Memories from around the world
This is a young museum, and this page is still waiting for its first voices. The memories people send reach Taisei personally, and the ones that move him find a home here over time — always with the writer's blessing. Yours could be the very first for this game.
Share your memory ↑From the Museum's Screening Room
Challenger 1985 — The Sound of the Machines