Halloween is a Seasonal Event celebrated in the Council Lands. For the past few years, strange circumstances seem to befall the Serbule Region during this time.
According to Velkort, someone (again) transformed the Magical Alter in Serbule Keep into a Necromantic portal to another realm. A variety of Undead creatures poured forth from the Alter anytime it came in contact with a source of Necromantic Power.
A series of magical locked chests spawned around Serbule Keep. Skeletons and ghouls drop keys to open these chests. After a time, the Magical Alter returned to normal, but keys continued to be dropped by various species of the Undead.
Event Time
October 29, 2016 - November 5, 2016 (Alter returns to normal) - December 5, 2016 (Chest keys stopped dropping).