How much you use a weapon determines just how good you get with it as well as how you upgrade your skills on the way through. It kind of breaks the RPG mould, as you can be a magical warrior with great archery skills. The results can be quite entertaining, especially when 30 of th em are after you and you've picked up a friend or two and upgraded your armor (hit loads and occasionally heal! great fun!!)
You can even alienate whole towns for little more than doing the right thing and trying to follow the plot as best you can. There is a lot of free will in this game and it generally gives you the freedom to make massive mistakes and attack would-be allies! They're not just bad, they're world-wide conspiracy bad with one dragon that actually tries to help you as part of the critical path of the plot!
Unfortunately it's one of those games where the dragons are evil and therefore you and everyone else is generally trying to kill them. The game starts with a dragon - which is always a good start in my book. Skyrim is a little slow to get going, but it's very addictive once you start to get the hang of it. SKYRIM - give up on having a life outside this game!
