I'm still floored by the mod-driven evolution of the game. The final product I ended up enjoying is a very different experience from the out-of-the-box bare bones edition I first downloaded off Steam in November of 2011. Much more colorful, textured, richer sounding, and with greatly enhanced non-player characters and interactions, as well as a stunning array of enhanced player character customization options. And that was with an array of mods chosen for their consistency with the in-game lore and atmosphere. If I'd been so inclined, I could have introduced elements of anime fantasy, science fiction, or any number of items and monsters from other fantasy franchises.
Of course it saddens me that the best speculative fiction experiences these days outside of fantasy novels are in games and the occasional cable TV series. Movies aren't what they used to be, and it's been a decade now since a new science fiction novel gave me a sense of transport, wonder, or the feeling that I'd had some important preview of the future.