Monsoon worked as a mercenary in Asia and South America for different guerilla groups and drug lords. Extremely skillful in jungle warfare. Came in touch with Cobra when he sneaked up Gnawgahyde and a couple of Range Vipers on a patrol to find out what they were doing. With a knife to his throat Gnawgahyde nervously convinced Monsoon, instead of killing him, to offer his skills to Cobra Commander and earn big money.
Monsoon has a preference for doing missions in rainforests, especially during the monsoon when normal people stay sheltered.
Monsoon most likely has a background in special forces, but it is unknown where he's originally from.

Tunnel Rat's head is quite recognizable. I did my best to change it into something very different, adding a beard and Recondo's hat.
The arms seemed to be cast in a soft plastic. That was hard to work with, which is visible at the elbow joints

I like this custom a lot. Every time I look at him, a little voice tells me he looks too good to be a Cobra.