The Tuchux are one of a number of independent organizations which participate at Pennsic War in the SCA. Primarily a North American phenomenon, Tuchux are barbarian personas based on a series of books - the "Gor" novels written by John Norman - who owe considerably more to popular depictions of barbarians in 20th century media than to the reality of so-called "barbarian" cultures.
Bluntly put, Tuchux dress like Conan and talk like Klingons. Leather, furs and maille are the norm, with lots of bare skin. The entire Tuchux subculture is very medjeeval, and many SCAdians therefore look down on them for their lack of authenticity.
In defense of the Tuchux, they throw excellent parties (especially at Pennsic) and they're pure hell on the battlefield. The chant of "TUCHUX! TUCHUX! TUCHUX!" is a warning to others to get out of the way before they charge, since Tuchux are content to mow down any allied unit in their line of advance.