Cyclops in dark messiah difficulty spoiler below...
They're ridiculously easy, really. ><
You just prepare a thrust attack, and poke them in the eye, as far as I recall. Then they lower down and you can stab them in it. If it doesn't die the first time you can just do it again. I don't recall ever having a problem with a cyclops after I figured that out... I think the 360 version will be a nice easy source of 1000 gamerpoints, unless they make crappy, tedious multiplayer achievements like Gears of War's kill 10,000 people
