Age of Wonders III is a turn-based strategy game that immerses players in a high fantasy world where they assume the role of political-military leaders. The game expands on the 4X gameplay model, allowing players to explore, expand, exploit, and exterminate as they build their empires through warfare, diplomacy, and colonization. New to this installment is the integration of role-playing elements, enabling players to customize their leaders by selecting from six distinct races—humans, draconians, high elves, dwarves, orcs, and goblins. Each race offers unique abilities that influence gameplay, along with six leader classes that provide various strategic advantages.

In addition to traditional empire-building, players can engage in quests offered by independent cities and forces, enhancing the gameplay experience with rewards such as gold or equipment. Age of Wonders III features a story-driven campaign with two playable factions, alongside single-player scenarios, online multiplayer options, random map generation, and a map editor. The shift to 3D graphics enhances the visual experience, marking a significant evolution in the series.