The first type of this enemy encountered in the game is the Black Ninja, which specializes in rapid short-range attacks. They are also the most common of this class and are usually encountered standing inside buildings, blocking important doors, or otherwise employing teamwork tactics in open areas. They wield an unspecified model of Japanese sword, most likely inspired by the ninjatō of popular culture (fictional and heavily featured in martial arts films and media) or the more historically accurate katana, which they use to relentlessly pursue Gex in an effort to damage him with horizontal slashes.
The second kind found in the game is the Red Ninja, which specializes in both close and long range attacks. This variation features more refined tactics, first concealing themselves among shadows and corners and unexpectingly growing to their full size in an effort to ambush Gex. Upon being encountered, the Red Ninjas will throw hira-shuriken (colloquially known as "throwing stars") towards him from a distance, switching to the same swordplay used by their brethren when approached. Both Ninja classes require two hits to be defeated.
Appearance and inspiration
The Ninjas in the game are based on the archetypical popular culture icon, rather than the historical figures that serve as its inspiration. This is accentuated by the fact that they wear the shinobi shōzoku uniform that has become widely associated with them. Despite this, the garb does feature a mon, kamon or monshō, a traditional Japanese emblem used to identify an individual, institution or family, in its backside which actually resembles some real examples.
The inclusion of the class as an enemy was inspired by them serving as the stereotypical mysterious and dangerous enemy in martial arts film during the decades leading to Gex: Enter the Gecko's release. The principal culprit most likely being the "Ninja boom of the 1980-90s", which began with Enter the Ninja and produced notable film examples including Ninja Vengeance, 9½ Ninjas!, 3 Ninjas, Beverly Hills Ninja and the Teenage Mutant Ninja Turtles, video games headlined by SEGA's Shinobi series and which has experienced a renaissance with films such as Ninja Assasin and The Warrior's Way as well as games such as Ninja Gaiden, Fuit Ninja and Metal Gear Rising.