Dyrrn is one of the 6 known daelkyr that are currently imprisoned in Khyber. It's lair connects to the Eldeen Reaches and the Mror Holds, and the dwarves are constantly battling its forces.
Most daelkyr follow a theme, and the abominations that they create reflects this. Dyrrn seems unique amongst them in that this doesn't seem to be the case, Dyrrn simply wants to create things from other things. Whilst all daelkyr can mold flesh, Dyrrn is seemingly the most prolific of the daelkyr when it comes to creating symbionts and other aberrations, and in particular it is credited with the creation of dolgrims, dolgaunts, dolgarr's, mind flayers, and neogi.
Kalshana and Warden encountered Dyrrn briefly via the Orrery in the Citadel of the Closed Circle.