Well, Abe is different to the mudokons, just like Phleg, I think... :fuzconf:

Abe's skin is blue, his hair is brown (not sure), he's surely smarter than the others (well, except Bigface), he won't get sick from brew, he has a stich on his mouth, so Phleg is not alone. :D

I think I got the awnser...
Phleg was a punk glukkon when he was young.
his differnt collor and hace can be because the strange "substances" he take when he was in his punk period