[Gayalondiel]

a lot of filmmakers will do that - increasing the size and ability of a bad guy. There are a few plausible reasons: it makes choreography easier and gives the battle a focus/ the bad guy seems much more threatening if he's bigger/ you have to generate less smaller bad guys if you have one big one. (ok, so that doesn't really apply here...)<P>Also, it gives a reason for how it was able to hurt both Frodo and Strider. When you look at the ease with which they kill off regular orcs, it works better if an obviously superior warrior/beast does any significant damage.<P>Or it could just be that PJ wanted a big troll. Look at Jurassic Park: Spielberg decided that Velociraptors were not threatening enough in real life, and so doubled their size for the film.