Tonka: The way I defeated him was by walking all the way to the RIGHT on the top-floor... walking around on the bottom floor is a pain in the neck, as you don't have a single minute free... the problem on the top floor though is, that the left and right tentacle arms keep throwing you down.. that is why you need to go all the way to the right, cause the tentackle arms cannot reach you there...
The next problem is that the tentackle arm are then in the way of you shooting at the midget in the middle, but if you shoot at the tentackle arm with a pumpgun, it will retract into the wall for some time.... shoot the tentackle arm so it retracts, and then go for the eye... as soon as you hit the eye, the midget's "shell" open up, and this is where you need to be FAST! ... use your riffle with scope, ... zoom in on the midget's head and fire as many shots as you can at him... it's the ONLY way to kill him!
When the shell close, or the tentackle comes out again, you have to do the whole thing over again...
once in a while the head makes a series of "headbuds" onto the top floor... but these should not hit you, if you're just far enough to the RIGHT... if you somehow get thrown down, then don't waste time down there... get right back to the top-right floor and continue.
When you've shot him enough times he'll die...
I can tell you, that when the game is completed, you'll get an infinite rocket launcher... now that help a damned lot the next time you play the game
... he'll only need two shots with this thing
... in fact that launcher pretty much sweeps everything you can encounter away...
and you don't want to get too close to these, or they drag you to them with HUUUUGE long arms, and plant their teeth in your shoulder, ripping a large lump of you, still having bloodvessesl dangling from their mouth when you wrestle yourself free! 
). I quickly swapped over to a rocket launcher and twatted him. Only took on shot, too!
