If you grew up in the 90s, there is a good chance that Captain Tsubasa Vol. II: Super Striker (キャプテン翼II スーパーストライカー) was part of your childhood. Released for the Famicom/NES by Tecmo in 1990 and based on Yoichi Takahashi’s famous manga, it turned football into a tense, command-driven game: pick a move, spend your guts, and hope your hero lands the Drive Shot or the Cyclone before the goalkeeper stops it.
For the millennial generation, it was more than a game. It was a cartridge on a borrowed console, a story told in Japanese we could not read, and a friend sitting next to us figuring it out one button at a time.
The password screen
The game has no battery save. To continue later, you write down an 18-character password made of Japanese kana and enter it on the input screen. That password stores everything: the round you reached, the level and experience of your players, your special shots, and even Misugi’s guts.
Back then, a password was either copied from a magazine or lost forever. Today we can generate our own.
The tool
I built a password generator so you can start from any round, with any player levels:
Open the Captain Tsubasa II Password Generator
What you can do with it:
- Pick the round. All 33 official rounds are listed with their opponents, from Fluminense in the opening round to Brazil in the World Cup final stage.
- Tune every player group. Set the Level and Exp of each of the ten groups. The players shown follow the current round: São Paulo, Nankatsu or Japan.
- Unlock abilities. Toggle the Cyclone Shot, the Drive Overhead Shot, and whether Misugi’s guts are lower than 100.
- Roll the dice. Random match randomizes the whole setup, with player levels suited to the chosen round. Two alternatives ignore the round: true random with levels within 5 of each other, or unbalanced with levels up to 30 apart.
- Follow along in the game. The password updates as you type, and the Game input screen highlights the exact key to press next. Use
<and>to step through all 18 characters. - Switch language. The input screen can be shown in Japanese kana or in the English version’s character set.
Everything runs in your browser, with nothing to install and nothing sent anywhere.
Rebuilt with AI
I did not invent the algorithm. It comes from the password generator by cah4e3, with the algorithm details credited to Gennadiy_Master. That tool has served the community well, but its interface shows its age.
With the help of AI, I rebuilt the same algorithm in plain HTML, CSS and JavaScript with a cleaner, more modern interface: steppers and sliders instead of raw fields, a highlighted input keyboard, tooltips that explain each option, and a layout that works on a phone.
Under the hood, the password packs the levels, experience, round, flags and a 6-bit seed into 18 six-bit values. It then adds a checksum, scrambles the values with a substitution table, and shifts each one by a running offset. The seed has no effect in the game, but changing it gives you a different and equally valid password for the same setup.
Now grab your emulator (or that old Famiclone), pick your round, and score a few goals for old times’ sake.
Note: You can play the game online at https://www.retrogames.cc/nes-games/c/index.html.