Thunderholme Thunderholme was a dwarven kingdom in the region known as the Thunder Peaks . Dwarven legends spoke of the city as favored by Dumathoin , the Keeper of Secrets Under the Mountain , and that it was home to the noblest miners and finest metalsmiths in the Realms . It was also said that its vaults were emptied in a day , when Dumathoin swept his chosen away to live in paradise with him . The truth however was far more horrible and tragic . The realm fell into decline when its king and heir were assassinated , and then was finally conquered by Aurgloroasa , a powerful shadow dragon , in 1054 DR . History . In 616 DR , scouts from Thunderholme noted the arrival of a powerful and potentially dangerous dragon called Aurgloroasa in the region but the dwarves chose to do nothing about it . This choice would eventually lead to their doom . In 989 DR , miners from Thunderholme accidentally expanded their delves into the lair of Aurgloroasa , rousing her from her centuries - long sleep . She immediately despatched the miners and caved in their tunnel to make it appear as an accident . but the damage had been done . She became interested in Thunderholme ' s operations and observed the dwarves via divination magic and spies summoned from the Plane of Shadow . In 1001 DR , Aurgloroasa began to whisper dark promises in the ear of the High Old One , the high priest of Dumathoin , Dagan , son of Belgin , Blood of Jangarak , goading his ambition and desires . He became obsessed with death , naming the voice " The Sibilant Shade " , a title that pleased Aurgloroasa greatly . Her advice fueled his obsession and he gradually rose to power and prominence , becoming second only to King Emerlin III himself . In 1034 DR , King Emerlin III died mysteriously in his sleep , leaving no heir as his son had recently disappeared on a trade mission to the Sembian city of Selgaunt . Having no other option , Dagan of Dumathoin was named royal regent . One of his first orders was to commission a grand temple of Dumathoin , a task that would gradually grow to obsession . In 1054 DR , the Priest Regent unveiled his magnificent temple in a grand dedication ceremony attended by every dwarf in the city . He then shocked the population by dedicating his new temple to Null and not Dumathoin , naming it the Necropolis of the Wyrm and then summoned Aurgloroasa , whom he believed to be his god ' s avatar . The dragon then proceeded to kill all but about thirty dwarves , many of who were later hunted down and slain in the following weeks . By the 14th century , the halls lay dead and empty , the hammers and forge fires silent . The only occupants were the restless dead , the countless hordes of dwarven nobles , warriors , merchants , and commoners that wandered the halls as skeletons , ruled by their deathly queen , Aurgloroasa , " the Sibilant Shade " . Features . Thunderholme was known to employ Dethek runestone s to bypass wards and gain entry to the city . A runestone was a magical stone tablet carved with dwarven runes and used to open magically sealed or hidden doors . When the city fell , Aurgloroasa may have slain every dwarf that escaped but did not recover every runestone . Four runestones surfaced in the 14th century , two in the hands of the Cult of the Dragon , one in the hands of adventurers , and lastly , one in the vault of an adventuring club in Harrowdale .