Blurk was originally created by Eclipse the Darkling as the future and stronger generation of the Black Arms. When Blurk was still a larva in an egg, it and its kind were taken to Sonic's World on-board New Black Comet so they could feed on and grow stronger on the local life. When the New Black Comet was about to be obliterated by Team Dark and the Spider Troupe however, Blurk and the Dark Arms' eggs were loaded onto an escape shuttle with Eclipse and sent down to Sonic's World so the future generation of Black Arms could survive.
The shuttle eventually crashed in the Red Mountain Zone on Angel Island, where Blurk was one of the few Dark Arms surviving the landing, along with Cyzer, Cregal, and Rhygenta. After being found, Cyzer was tamed and raised by Eclipse, who swore vengeance on Shadow for killing the Black Arms and Dark Arms. Following some days of nurturing, Eclipse left Blurk and the others to find a better source of power to make the Dark Arms stronger.
Blurk is a small Dark Arm with a cube-shaped body and a cyan-glowing mouth with serrated teeth. It has three blue eyes with thin pupils on the frontal vertical sides of its body, black skin and four small tentacles for legs.
Blurk is a fierce Dark Arms hatchling with bad manners who, according to Eclipse, does not chew its food properly.
- Blurk's name is a portmanteau of its secondary color, "blue", and its appearance shape, a "block".
- Blurk's design, like most Dark Arms hatchlings, is reminiscent of one of the Wisps, specifically the Blue Wisp.