This project has an odd, nearly incestuous history. It was a film pitch of a theoretical graphic novel, then a graphic novel using shady chicanery for sales to spur a film, then a film that reinvented itself into a reiteration of genre films.
Besides combining the two genres of Westerns and Sci Fi, it loops or inverts other conventions. It is essentially John Carter Of Mars in reverse: instead of a frontiersman transplanted to an alien world, it is an alien world invading the wild frontier. It is also a causal loop between James Bond and Indiana Jones: Bond was the key inspiration for Jones; Harrison Ford turned out to be the son of Sean Connery in the third Jones film; and here, Daniel Craig meets Harrison Ford in a rustic adventure romp. Additionally, Han Solo was a cowboy, down to the vest and the cantina duel; before there was any hint of a third Star Wars trilogy finally happening, this Western was also the closest chance to seeing Ford being in Solo mode again.
Jon Favreau (Iron Man) adapts the comics concept in the loosest sense, going to great care to evoke all the methods, hallmarks, and even film stock of the best Western classics. There are also quiet winks at SF classics along the dusty trail. The film, an enjoyable rollick with some twists, made its budget back but audiences seemed to take it for a novelty. The extended cut is the best version, such as deepening the interplay between Ford and Adam Beech, his spiritual son.