It all comes from the pygmies of west africa. They are short stealthy hunters that use blowguns and ranged weapons in their hunting.
I think there is a conan story with little men in the jungle. But I am not sure.
But yeah the idea seems like it came from The Mummy Returns. However, the mummy returns isworking off a lot of fantasy tropes. One being the airship, another being the scepter, etc etc. I think that some movies and books capture an idea so well that it becomes a normal element of fantasy.
And could you think of any other way to use undead halflings in a jungle? I mean can you think of any other way to use orcs in a former dwarven city than as they are portrayed in LotR?
I see the use of the undead halflings as "if the shoe fits, wear it." I think people put too much emphasis on originality these days. Originality is good, but so is borrowing (a nice way to say rip off). The Mummy returns did not have a Lich beind everything at the end so I figure that the rip off is ok.
Another point about originality is that much of this game is not original. The whole thing is derivative in some way or another. If you read enough swords and sorcery along with enough classical and medieval history, you realise that there are few things in the game that are not derivative, borrowed or just straight "rip offs."]
Aaron.