The Sundering: Rise of the Witch King is a mod for Medieval 2: Kingdoms and based around the fantasy world of Game workshop's Warhammer universe during the civil war between the Elves, the mod's campaign opens with the Death of Bel Shanaar in -2751 IC.
The armies of the Tomb Kings often include units of Skeleton Horsemen, cavalrymen who fight on in death much as they did in life, scouting ahead of the army and harrying enemy outriders as they advance. The Horsemen sometimes fight as armoured units, charging head-first into the enemy, aiming to break them with a well-timed charge. Their main role on the battlefield however, is as a scouting force, where they will advance along the flanks of an enemy army, peppering them with well-aimed shots from their bows before they gallop away from any harm that may befall them.