Oath Champion War is a free-to-play tactical puzzle game available on Android that immerses players in a medieval strategy adventure. Players can deploy various units such as Footman, Archers, Knights, Clerics, War Mages, and Titans to defend their castles and conquer enemy strongholds. The game features a unique energy management system that requires strategic deployment of units while managing limited resources. With a story-driven campaign, players navigate through a royal campaign map, unlocking new battles and challenges as they progress through multiple chapters.

The gameplay in Oath Champion War emphasizes tactical combat with wave-based enemy surges that increase in difficulty. Each unit type presents unique strengths and costs, requiring players to think critically about resource allocation and unit deployment. Special abilities known as Oath Powers can be built up for powerful attacks, adding depth to the combat experience. The medieval-themed visuals and intuitive controls enhance the overall user experience, making it an engaging choice for both casual and dedicated strategy enthusiasts.