Expedition: Into Darkness is a role-playing game for Windows that immerses players in a perilous journey through ancient ruins. In this game, players can embark on solo adventures or team up with up to four friends to explore forgotten dungeons filled with nightmarish creatures, traps, and hidden dangers. The game emphasizes strategic gameplay, where death results in permanent loss of character and inventory, encouraging players to tread carefully and make wise choices during their quests.

Players have the ability to customize their characters and gear by assembling weapons from various components, including swords, axes, and bows, tailored to match their preferred playstyle. Additionally, the game introduces a unique mechanic where players can forge deals with dark gods for powerful abilities, albeit at a cost. Resource management plays a critical role as players gather materials to upgrade their base camp, enhancing their chances of survival and success in future expeditions.