In the late 1840s, the California Gold Rush called thousands of pioneers West, traversing the treacherous Sierra Nevada mountains in search of fortune. In Sierra West, you take on the role of an expedition leader, guiding a group of rugged trailblazers on a journey filled with strategy and tactics. The game's major highlight is its four included thematic modules – Apple Hill, Gold Rush, Boats & Banjos, and Outlaws & Outposts – each with special cards and components that combine with the basic game elements to create unique play modes. Before each game, players choose one of these modules, building an overlapping 'mountain' of cards that defines the scenario and specific rules for that adventure.

Each turn, you arrange three cards on your personal player board, cleverly overlapping them to expose or conceal action icons. This creates two distinct paths for your pioneers to follow, from left to right, executing a series of small actions. Common actions include claiming cards from the mountain, building cabins, gaining resources, and advancing your wagon. The chosen module adds thematic actions, such as harvesting apples, mining for gold, fishing, or fighting outlaws. As your pioneers complete their paths, they gain access to action spaces on the upper portions of your cards, where they can exchange resources to progress on scoring tracks or activate special module abilities. As the mountain is explored and more cards are revealed, new opportunities and challenges emerge, extending a row of cards that offers more options and intensifies the experience. Sierra West is a highly thematic Eurogame that reinvents action programming, worker placement, and deck-building, and also features a solo mode designed by Dávid Turczi.