Battle of Keeper's Dale

The Battle of Keeper's Dale, known as Yvonnel's Folly by the drow, was a short war fought by Clan Battlehammer and their allies against the drow of Menzoberranzan and their slave army of humanoids.

Location
The environs of Mithral Hall.

Causes
Matron Mother Yvonnel Baenre had wished to conquer the surface world in the name of Lolth for most of her considerable lifespan. Flush with power from her successful eradication of House Oblodra, Matron Baenre pressed ahead with a previously delayed plan to assault Mithral Hall, home of the dwarves of Clan Battlehammer. Possessing the trapped Gandalug Battlehammer, Matron Baenre had gained the knowledge of the city's defenses and was confident that victory would be hers.

Recently returned from an excursion to Menzoberranzan, Drizzt Do'Urden came back armed with the knowledge that the drow were coming to Mithral Hall, and so King Bruenor Battlehammer appealed to his allies for aid. Longsaddle, Settlestone and Silverymoon responded, pledging significant numbers of men for the coming war. Nesmé sent men as well, but only a small number - their relations still strained with the dwarves.

Once the drow had marched from Menzoberranzan, clearly on their way to Mithral Hall, Belwar Dissengulp, a friend of Drizzt's, was given leave to command a force of deep gnomes from Blingdenstone. Limited by Blingenstone's King Schnicktick to 300 warriors, they left with haste to help defend Mithral Hall.

Battle
The dwarven Gutbuster Brigade, Companions of the Hall and thousands of dwarven warriors fought valiantly and effectively in the tunnels beneath Mithral Hall, collapsing possible entrances to the Undercity whenever it looked like they would be overwhelmed. Despite the efficacy of their defense, the drow had the advantage, forewarned of most of the tricks and tactics arrayed against them, they broke through into the Undercity quickly, though with higher than anticipated casualties, including Uthegentel Del'Armgo at the 'hands' of Bidderdoo Harpell. At that point, on the advice of Methil El-Viddenvelp, Jarlaxle commanded his Bregan D'aerthe mercenaries to begin avoiding the fighting while the drow marched their reserve forces toward the Undercity.

While a division of dwarves held the eastern side of Keeper's Dale itself, the humans, under the nominal command of Berkthgar, fought off a second wave of foes on the western side. Armed with magical pellets that would counter drow darkness abilities and blind their foes, the humans appeared to have the upper hand, especially since the drow did not fight with any real semblance of unit cohesion - selfish by nature as drow were. However, despite these apparent advantages, the humans were horrendously outnumbered and quickly outmaneuvered. Drow wizards blasted apart men and only a drow tactical misstep combined with the magical might of Alustriel Silverhand saved the human force from being massacred. Shortly afterward, the deep gnomes emerged from the Underdark onto the surface not far west of the fighting and opened a second front behind the drow lines. Besnell, the elven commander of the Knights in Silver detachment was felled by goblins shortly before the remaining human forces, depleted to roughly two thirds of their original number, could regroup. Dawn was the real turning point in this battle. As the rising sun blinded the drow army, Berg'inyon Baenre, who led the surface assault, was filled with doubt and quickly issued a retreat order.

The Companions of the Hall had decided early on that the only way to ensure victory would be to eliminate the drow commander, whomever that might be. Drizzt was dismayed when he saw Yvonnel was leading her forces herself when they came upon the drow command post hidden in tunnels behind the enemy line. With no choice but to attack the command post, they did so with vigor and determination. Unknown to all assembled, a glabrezu beholden to the balor Errtu had brought a sapphire with it when summoned that radiated an Antimagic field. On orders, it released the sapphire from a protective case when the Companions attacked. With the drow so highly dependent on magic, the Companions took the initiative to bring their superior skill-at-arms to bear during the instant that the drow were denied their protections, eliminating all of the assembled drow priestesses before they could recover from the shock.

Aftermath
Matron Zeerith Q'Xorlarrin ordered a retreat from Mithral Hall's Undercity, more concerned with her own status than continuing the fight. Berg'inyon's forces regrouped with Bregan D'aerthe on the way back from the surface. Triel Baenre, as Yvonnel's heir cemented her much more shaky rulership over Menzoberranzan, later going on to conquer Blingdenstone as a show of power and act of revenge for the help they gave the dwarves. Many of the city's refugees went to live in Mithral Hall, where they were welcomed.

Although tinged with great sadness over their losses, the victory of the surfacers was hearty. Berkthgar began talking about and eventually took his remaining followers back with him to Icewind Dale whereupon Settlestone was repopulated by dwarves. Terrien Doucard took over from Besnell. Drizzt and Catti-brie left the Hall to go adventuring and King Bruenor abdicated his throne to Gandalug, taking Regis and a few loyal dwarves with him back to Kelvin's Cairn.

Casualties
Notable casualties included the deep gnome Firble, Regweld Harpell, the Silver Knight Besnell, Auro'pol Dyrr, Uthegentel Del'Armgo as well as Quenthel, Bladen'Kerst and Yvonnel Baenre.