Rustler is very much like an old-school Grand Theft Auto game, in a couple of ways. It's a top-down action game in which you'll commit all sorts of heinous and bizarre crimes and quests, and it takes place in what developer Jutsu Games describes as "historically inaccurate medieval setting" filled with "humor, anachronisms, and pop culture references."
You'll play as The Guy, a local peasant in an uncaring world who's forced to deal with medieval justice, witch hunts, the Inquisition, and worse. You can complete "twisted" missions and quests, or opt to ignore the plot and do whatever tickles your fancy in the moment: Steal a horse, do some cage fighting, join up with the Round Earth weirdos, or get into a cart-drifting race. There's even a Grand Tournament to join, if you really want to make a name for yourself.
It all sounds rather ridiculous, and that's clearly the intent: The game's soundtrack, for instance, is provided by a bard, "your sweaty personal radio," who will change tunes based on the action on-screen—or you can adjust the music manually by punching him in the face. "Form weird alliances, double-cross your foes, and dig up dinosaur skeletons in a light, easy-to-understand, and hard-to-empathize-with story," the Steam page says.
Rustler has been available on Steam Early Access since February and is set to go into full release on August 31, with new subquests, storylines, safehouses, enemies, animals, and bug fixes, which are listed in full here. If you'd like to get a look at all the new content, the 1.0 update is available right now on the Early Access beta branch.