Head, arms and torso: New sculpt Iron Grenadier
Waist and legs: Wave 7 Snake-Eyes
Vest: DTC Barrel Roll
Pouches and Boonie Hat: bbi
Machette: Plague Troopers 6-pack
M-4/shotgun: Custom Marauder Inc.

The United States Naval Special Warfare Development Group, otherwise known as NAVSPECWARDEVGRU, the NSWDG, or simply as DEVGRU, is the United States Navy's premier Counter-Terrorism unit. It is officially stated to have been formed after S.E.A.L. Team Six was "disbanded".

However all Spec Ops operators know S.E.A.L. Team Six was not disbanded, just re-tasked as the G.I. Joe team. Each member of the G.I. Joe team has a specific mission specialty within the many tasks and trainings of a Navy S.E.A.L.

I make these guys so fast, that I don't have time to come up with a back story.
The ideas that I had in mind were:

He makes Recondo look like a mama's boy.
His name is feared by the Jungle Vipers
His codename is from what the locals call him after he ate a King Cobra while dining with them to gain their favor, that and how many Cobra agents he has eliminated.