King Hiss is probably the least known of He-Man's major enemies (after Skeletor and Hordak), mainly because he never appeared in either of the cartoon series in the 80s.
He did finally get some air time in the second series of the 2002 series, where he was the major villain, supplanting Skeletor both as an antagonist, but also as the occupant of Snake Mountain (which, unsurprisingly, was was the capital of the Snake Men).
King Hiss has the power to transform the top half of his body into a writhing mass of snakes, an ability which was extremely poorly conveyed in the original toy, where a plastic upper torso popped off to reveal a squished mass of snakes and meant that the toy was in no was posable.
When it came to painting, I kept things simple with a series of base colours coated with washes. MotU miniatures allow for this sort of simple approach as the original colour schemes were designed to be rendered in cheap plastic with limited painting required and so lack detail.
The only areas I consistently change are the weapons and equipment because these were always single colour plastic and I think a lurid green staff and a bright red shield might look a bit weird.
Having now done King Hiss and Kobra Khan, I might have to track down suitable miniatures for some of the other Snake Men. I'll probably hunt for proxies rather than wait for someone to make them as lots of fantasy ranges have serpent man races I should be able to use to create approximations of characters who are less than iconic in their appearance.
I've had a bit of a splurge on some miniatures for several different projects (40k, 7TV, LotR), so the acquired tally has taken its biggest hit in a while. However, I'm hoping to plough through some of these fairly quickly.