The Elder Scrolls games have been brilliant for long time: huge open worlds that let you go wherever you fancy, get wrapped up in hundreds of different stories, and make a life for yourself. But until Skyrim, they weren't particularly good at one of the most exciting things about other RPGs: levelling up.
You levelled up, of course, but you didn't get to spend any terribly valuable points on any terribly exciting skills. In Skyrim, you do. It's the perfect compromise between a traditional RPG and the organic practice-based system of previous Elder Scrolls games. You still get incrementally better at whatever you do, but each level gets you a perk point, and the perks on offer are absurdly tempting.
So your character adapts both to how you end up playing, and the grand ideas you have for them. I started out as an archer, but all the sneaking around made me stealthy enough to pull off backstabs. That was more satisfying than I realised, so I shifted towards it and improved it dramatically with perks.
The organic progression influenced my conscious progression, and resulted in a character build I hadn't set out to create but which suited my play style perfectly. I became an assassin who can hide in plain sight, vanish mid-combat, and kill almost anything in a single strike. I'd tailored my own custom stealth god, through 84 hours of practice and 41 perk choices.
Now I'm working on a tank: an unstoppable orc clad in hand-crafted brass, with a shield the size of a small country and an axe I've sharpened beyond anything money can buy. I already have a perk that lets me bash people away with my shield, and next, I want the one that lets me knock everyone flying when I sprint at them. Then I'm making an illusionist.
It's a sense of excitement I never had with Oblivion. When I started again in that game, it was usually because I'd messed up my character. I start again in Skyrim because there are so many possible characters to try, lives to lead, possibilities to explore that it would be rude to the developers not to seek them out. That, to me, is the definition of a great RPG.
Read our Skyrim review for more.