Kingdom Under Fire: The Crusaders is the sequel to Kingdom Under Fire: War of Heroes and continues the storyline 50 years later.
Kingdom Under Fire: The Crusaders is a real-time strategy game that alternates its gameplay with hack and slash style of Dynasty Warriors combat and adds some minor role-playing elements. Before entering battle, the player can control where he wants his various units/armies to go via a mini-map. When the main character's army engages in battle with the enemy, the gameplay switches to real-time controlling third-person hack and slash combat.
Kingdom Under Fire: The Crusaders includes these unit types:
- Airborne Units - Engages units from the air. Only archers, special ballistas, and magic can attack them.
- Archers - Fire at air and ground targets. Dark Legion archers can fire from horseback.
- Artillery - Engage units from long range.
- Cavalry - Disrupts enemy ranks and causes massive troop damage.
- Infantry - Basic melee units.
- Mortars - Fire at ground targets and can take down castle walls. (Human Alliance exclusive)
- Orc Ghouls - Orcs risen from the grave that have high defence but are vulnerable to holy damage. They can be sent to destroy a siege weapon as a suicide bomber.
- Sappers - Lay traps that damage the enemy and can set fire to forests. Sappers can be used as a substitute for infantry. Human Alliance sappers lay mines which yield greater damage.
- Scorpions - Can be used as infantry or take down castle walls as infantry. Scorpions are immune to arrow damage. (Dark Legion exclusive)
- Spearmen - Special infantry units that can immobilize enemy troops in front of them and can take down cavalry. The Dark Legion version of spearmen are orc axemen.
- Support Units - Units that can cause massive damage to the enemy. These units can be bomber wings, dirigibles, storm riders, swamp mammoths, or wyverns.
Kingdom Under Fire: The Crusaders has online multiplayer in gametypes such as head-to-head and deathmatch. Online ranks were kept on leaderboards.