He played Mappy every day — then built his own game from what he loved.
Ryuichi Nishizawa was nineteen when he joined UPL, a small game company in 1984 that gave its developers almost total freedom. There was a Namco game he loved — Mappy, a side-scrolling platformer about a mouse chasing cats through a mansion. He played it every day at an arcade near his house, trying for the high score, studying the character design and music. When UPL asked him to make a game, he started from that feeling. Ninja-kun: Majou no Bouken became a vertical-scrolling platformer, not a copy of Mappy but a shape it inspired. It wasn't about stealing ideas — it was about learning from what moved you. When you love something enough to play it every day, you're already studying it. You just need permission to build from what you learned.
— inspired by Ryuichi Nishizawa
About this game
Released for Famicom in 1985, Ninja-kun: Majou no Bouken is a vertically scrolling platform game where players climb upward through three repeating stages of increasing difficulty. The player attacks enemies with shurikens and can jump on their heads to stun them. Collect three orbs to unlock a bonus stage. Originally an arcade game by UPL in 1984, the Famicom version was published by Jaleco and became the foundation for their later Ninja JaJaMaru-kun series.
The Story Behind
Ninja-kun: Majou no Bouken originated as a 1984 arcade game developed by UPL with Ryuichi Nishizawa handling game design, character design, background design, and programming. UPL maintained a development culture with no content requirements, allowing creators to pitch ideas freely. The Famicom port was released by Jaleco in 1985. Jaleco later wanted to create their own ninja-themed series but, since Ninja-kun was a UPL property, they created the similar but distinct Ninja JaJaMaru-kun series instead.
Tricks & Tales
Nishizawa drew inspiration from Namco's Mappy, which he played daily at an arcade near his home, particularly studying its character design and music. The game's vertical scrolling design — climbing upward through multi-tiered cliffs — was a distinctive technical feature for its time. UPL was generous enough to allow developers to credit themselves in games and advertise in demo loops that titles were developed by small teams.
Collector's Guide
Region & Compatibility
Famicom and NES are the same hardware family but use physically incompatible cartridge formats — Famicom carts have a 60-pin connector and a narrower shell, while NES carts use a 72-pin connector with a wider housing. You cannot insert a Famicom cartridge into a North American NES slot without an adapter, and vice versa. The Famicom itself has no lockout chip, so any Famicom cartridge from Japan will run on a Famicom console regardless of origin. If you are buying a Japanese Famicom cart to play on a NES, you will need a 60-to-72-pin physical adapter; if you own a Famicom, Japanese-market software is your native format and no workarounds are needed.
Maintenance Tips
The gold-plated edge connectors on Famicom and NES cartridges pick up skin oils and oxidation over decades — a gentle wipe with a cotton swab dampened in 90% or higher isopropyl alcohol, stroking along the length of the pins rather than across them, is the accepted standard. Let the alcohol fully evaporate before reinserting. The old habit of blowing into a cartridge is folklore: the moisture in breath causes slow corrosion of the contacts over time, and any improvement you felt came from the act of re-seating the cart, not from the breath itself. Nintendo eventually updated its own troubleshooting guidance to say explicitly: do not blow into your Game Paks.
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 Ninja-kun: Majou no Bouken copies regularly.
My Ninja-kun cartridge won't start — what should I do?
The most common reason is dirty contacts on the cartridge pins. Gently clean the gold pins with a cotton swab dampened in 90%-or-higher isopropyl alcohol, wiping lengthwise along the pins. Let it dry completely before inserting it. Never blow into the cartridge — the moisture in your breath gradually corrodes the very contacts you're trying to clean.
Before You Buy
Things worth knowing before you buy Ninja-kun: Majou no Bouken
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.
See the unit we have →Unexpected Discoveries
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Rooms this game lives in
Wander deeper — explore the themed rooms where Ninja-kun: Majou no Bouken 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.
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