Plus the code is ROCK SOLID and always has been -- it hardly ever crashes. Yet it's like a pinball machine with 5 million balls in play, and still amazingly fast.
And starts reasonably quickly.
And runs really well on Linux, with no quirks or hicups.
(As someone who uses a Linux machine as the "primary" desktop, only switching to a Windows machine for games and other things that need it, I find it really nice to have a quick-to-launch game that runs perfectly on Linux.)
Also the beautiful hires Czechnological artwork.
It's top-notch design, execution, and graphics.