Revolver Ocelot, or Shalashaska, is a fictional character who originates in the Metal Gear Solid video game series.

Ocelot specialises in military gunplay and interrogation. He is an ex-Russian Spetsnaz soldier who served during the Soviet invasion of Afghanistan. It was during this time that he became infamous amongst the mujahadeen as a sadist for which they christened him Shalashaska (a Russian slang word for "prison").

He is described as being obsessed with guns, cowboy films and spaghetti Westerns. This is reflected in his choice of dress as well as his codename and the weapons he uses - he is armed with two Colt Single Action Army revolvers, which he wields with almost superhuman skill, being both a master of ricochet and fancy gun-twirling techniques; by the time of Metal Gear Solid 2, he seems to have attained the uncanny ability to draw his weapon and shoot any target in the heart in a split second. As well, he uses a technique known as 'fanning', in which one hand holds the revolver and the other hits the revolver hammer repeatedly, allowing for 'automatic' fire. He was inspired to use revolvers after his first meeting with Big Boss when they fought each other. Big Boss, who was under codename "Naked Snake", watched Ocelot wield a Makarov and said his technique would be better suited for a revolver, and advised him to wield 2 revolvers for more ammunition.

In Metal Gear Solid he is a member of FOXHOUND, an elite special forces group, and in Metal Gear Solid 2: Sons of Liberty he works as a spy for the Patriots to create a simulation intended to create an ideal soldier on par with the legendary Solid Snake. He is in fact fooled by the Patriots, who use the events to test the S3 Plan.

Ocelot had a partial arm transplant performed in Lyon, France after his right hand was cut off in Metal Gear Solid. The operation was paid for by Solidus Snake, and the arm belonged to Liquid Snake, who died in Metal Gear Solid. In Metal Gear Solid 2, Liquid is able to take over Ocelot's mind and body via the arm, possibly because he (Ocelot) has inherited some of his father, The Sorrow's, abilites as a medium.

Ocelot is also featured in Metal Gear Solid 3: Snake Eater in his younger years. He is part of GRU and is Major of the Ocelot unit of Spetsnaz, although in reality he is a double agent working for the CIA. Near the game's end, it is implied that he is the son of two legendary members of the Cobra unit, The Sorrow and The Boss, with his year of birth being 1944.