Fighting Vipers is a 3D fighting game developed by Sega-AM2 and released by Sega for arcades (running Sega Model 2 hardware) on November 1995.
Utilizing the same game engine as SEGA-AM2's Virtua Fighter 2, Fighting Vipers is known for its armor-breaking system (where knocking away pieces of clothing leaves them more vulnerable to damage), mid-air recovery mechanic, and the first use of walled stages in a 3D fighting game (removing ring-outs).
Along with a crossover console spin-off with the Virtua Fighter series (known as Fighters Megamix) in late 1996 and a direct sequel in 1998, the game was ported to the Sega Saturn in 1996 (adding new game modes and other bonus content). The Japanese version of the Saturn port also features numerous in-game advertisements with the Pepsi soda brand, including the Japanese mascot Pepsiman as a hidden guest character. The original version was later ported to the PlayStation 2 (as part of the budget Sega Ages 2500 series) exclusively in Japan on April 28, 2005 and ported to both the PlayStation 3 (via PlayStation Network) and Xbox 360 (via Xbox Live Arcade) as a digital release (with online multiplayer added) on November 28, 2012.
The game includes eight fighters to choose from by default and one final boss (known as B.M.), who has a weaker playable version as a time-locked hidden character. The Saturn version makes both hidden characters unlockable and adds one hidden unlockable fighter (the bear Kumachan). The Japanese Saturn version also adds an additional unlockable fighter (Pepsiman).
Unfinished version of both Sonic and Tails (from Sega's Sonic the Hedgehog series) are unused characters hidden in the game. This concept was later used as the basis for Sonic the Fighters.