It's usually the case that if you're a fan of a video game and want to check out its concept art, you either look at some images online or you pay a lot of money for a big fancy book. League of Legends is trying to combine the two, releasing what amounts to a big fancy art book, only as a website, and it's 100 per cent free. It's simply called The Art of League of Legends, and is structured just like a book, only you click through it instead of thumbing through actual pages. There are sections devoted to Summoner's Rift and each individual Champion, as well as a roundup covering LoL's wider stuff like esports and pool party skins.
Even if you don't play the game, this is still a cool thing to go through if you dig game art in general, especially the pencil art sketching out each Champion.
I've included a selection of highlights below, but you should really check out the whole book.
Fine Art is a celebration of the work of video game artists, showcasing the best of both their professional and personal portfolios.