|Battle of Castle Aquilon|
|Part of Raids on the Riverlands|
|United Federation of Provinces|
|Commanders and leaders|
|Multiple squads, including the entire Redstonian Artillery Corps||Remnants and skirmish survivors|
|Casualties and losses|
|Small number of attacking forces killed||Majority of the entire garrison fled or captured - small number killed during skirmishes and artillery bombardment|
The Battle of Castle Aquilon was the final battle between the Redstone Alliance raiders and the defending United Federation of Provinces. The attack was planned in the keep atop Helmsdeep, today the headquarters of the Mercenary Bank, after which the military forces of the Kingdom of Redstonia, Kingdom of Kythira and the Kingdom of Helmsdeep moved to the Riverlands, hiding behind some hills south of the King's Mountains.
Having observed Castle Aquilon, they moved forward with their siege. As dusk arrived, the Helmsdeep military moved in. Whilst much of the Riverlander mercenaries had abandoned the castle earlier, a small military garrison still remained, able to hold the fortress. Upon the arrival of the Redstonian Artillery Corps, bringing with them the legendary Redstonian Cannons, the castle quickly surrendered. After moving in their forces, the Consul Republic was however nowhere to be found. Upon this discovery, the Kythirans, having gained intel about a federation bunker earlier, detonated a large bomb just outside of the castle, blowing up the bunker's ceiling and allowing the Kythirans to move in and kill the consul.
After the battle ended the few supplies left in the castle were split between the victors, whilst the Redstonian and Helmsdeep forces flooded the bunker and blocked the castle's roof, rendering it useless to defend the Riverlands. As a final insult, a large Helmsdeep flag was raised above the fortress, where it stood until the Kythirans removed in during the Third Era.