Rocko is a bounty hunter for IG-88.
Through unknown circumstances, the bounty hunter known by the nickname Rocko joined the Intercontinental Guards, Unit 88, where he got his nickname.
When a bounty was set for fifteen targets, whose heads needed to be taken to a castle in France for verification, IG-88 set out to claim as many as possible. Rocko was presumably a part of Demon's strike force as they infiltrated the Karpalov coalmine, where a number of targets would be gathered.
En-route to France, as a pair of MI6 agents began interrogating Weitzman, the plane was infiltrated by Knight and Schofield during the plane's refueling. After a chaff grenade jammed all of IG-88's guns, Rocko confronted Schofield and threw him out of the shattered cockpit window. Rocko then helped Cowboy stun Knight by smashing his specialised glasses, and then restrained the rival bounty hunter so that Cowboy could run him over with their Humvee.
However, Schofield rescued Knight at the last second, and the Marine and Rocko exchanged blows with makeshift shuriken knives until Gant hancuffed the big IG-88 bounty hunter to the Humvee. The recovered Knight then handcuffed Cowboy to a Humvee, and then sent the Humvee, with both the IG-88 men still cuffed to it, out the loading ramp, sending Rocko and Cowboy falling to their deaths.