Code Name: Viper

Code Name: Viper (Japanese: Ningen Heiki Dead Fox, known to Chinese retro gamers as Human Weapon) is a tough side-scrolling action shooter developed and published by Capcom, released for Famicom on February 23, 1990. It is widely regarded as one of the hardest games on the Famicom. Federal agent Smith is dispatched by his superior Jones to infiltrate drug cartel strongholds across South America, rescue captured agents and gather intelligence fragments. As the investigation unfolds, Smith pieces together secret documents and uncovers the shocking truth: his commanding officer Jones is secretly colluding with the drug ring. Smith heads back to headquarters to eliminate the traitor and take down the whole criminal network. The multi-level map lets you switch between upper and lower floors. You start with an infinite handgun and limited machine gun ammo. Enter hidden rooms to refill ammo and expand your maximum health up to four HP bars. Enemies include patrolling riflemen and heavy guards. Getting hit triggers stun with no temporary invincibility; successive shots can kill you instantly. Enemies often ambush from hidden spots, demanding precise reflexes and stage memorization. You must rescue hostages and collect intelligence fragments in the first seven stages to unlock the eighth and final mission at headquarters. Password save keeps your progress. Instead of many giant boss fights, it focuses on exploratory infiltration shooting with maze-like level design. It features realistic pixel art and tense atmospheric soundtrack. Widely bundled on Subor multicarts in China, its brutal difficulty and twist story make it a legendary spy-themed Famicom classic.

These are the default keys. Click the gamepad icon 🎮 in the player’s bottom toolbar to rebind them. Gamepads are detected automatically. On phones you get on-screen buttons.

1P

2P

The NES was always two-player — 2P uses the numeric keypad, and NumLock does not matter. No numpad? Rebind 2P to other keys in the 🎮 panel.