These Monstrous Mutations (scientists theorized were caused by the R.D.S. Virus) - first came wading in at the Island of Bermuda on December 31st 1999.
Humanity as a whole call them "Prometheans" - some of these monstrous R.D.S. mutations stand taller even than an Sentry, those that do either have little (or no) epidermis covering their bodies. Freely showing the muscles, sinews, and tendons that are normally hidden beneath the skin - and yet, they do not bleed (unless injured, which is hard to do). There are smaller Prometheans, usually naked - twisted in back and bone, or bloated - with a wide almost shark like mouth full of ogreish teeth.
The big skinless creatures have been classified by Varian Blackwood as " Inanis-Cutem" (lit. empty skin), whereas the smaller more stupid creatures are referred to as "Stultus" (lit. stupid) as they lack anything but the most basic intelligence.
There seeming random attacks on City States world wide - there is a lighting filled bank of fog, they appear - attack and then vanish just as quickly in the same way.