Note that you must complete The Giant Dwarf quest in order for Drorkar to appear in the Keldagrim Palace workshop on the west side of the river.
Dwarven technology tree items can be unlocked using Dwarven currency which is earned by completing Invention tasks (not to be confused with Daily Tasks). These tasks can be found at the noticeboard in the Invention guild, in Dorgesh-Kaan near Oldak, and in Keldagrim near Drorkar. Up to 5 tasks can be saved and each 12 hours a new task is added.
The structure of the dwarven tech tree is as follows:
|4||70||Dungeoneering lock melter||55|
At RuneFest 2015 the following device concepts were shown as examples of items that could be included in the dwarven tech tree:
- Mind-leeching device - would turn combat experience into skilling experience.