If you can't find how to start this dialog, check here how to trigger it.

Suddenly, the ground seems to rise up before you, a hail of dust and fury.

A spirit begins to form to the maelstrom, in the shape if a humanoid.

"At last enough energy comes for me to speak the truth! It has been so long since I have felt a single surge of energy in this plentiful land."

Who are you?

"I am the dead now. In my glory I was a noble architect, working with the finest materials and metals. Now I rot."

What are you doing here?

"I am resting here, as you can clearly see. This cursed land is truely my last resting place."

"I have waited here for someone of your power to come along, someone with the ability to hear the voice of the spirit on the wind. Never did I expect such concentration of force."

"Now I stand here on what may seem all to fragile matter, to tell you of the trouble that will befall you."

What trouble do you speak of?

"I speak of the trouble that Mastaba and his uncaring sons have brought upon this land. I can see them from here, convincing the poor souls to destroy each other time and time again."

"I do not know what evils must live in the hearts of such uncaring ones, nor do I wish to know. I have my own evils that I must endure."

What are these evils of yours?

"I once worked for the darkness, building ancient machines and barriers unwittingly. I had no knowledge of the destructive forces I was paid to manipulate."

"I had worked for Mastaba for many a year, building that cursed island fortress of his. I hope it now lies in rubble, the wretch deserves it."

"My servitude was rewarded with my death, a sacrifice at this spot to live out my existence in this waste. To this day I am haunted by thoughts of his subtle violence and corruption."

"Imagine, haunted spirits. It's not easy".

What can you tell me of Mastaba?

"I have nothing more to say of the man. The work that I was instructed to perform now troubles me, and I am ashamed of the wasted life and time that went to his hungry palate."

"I hope he stays trapped in that infernal device of his forever. Unfortunately, I know that this is not possible, though, as some Fool is sure to release him eventually. A necessary evil, I'm afraid."

Device? What is he trapped in?

"No one knows for sure what exactly the device is. Mastaba always referred to it as a temporal containment sphere, though I have no idea what that might be. Some sort of time travel device, I'd guess."

"Who knows what this actually means. I have often pondered here in  my slumber, of the reason for this madness. I have not found a reason yet that meets any logic, but I'm sure his plot is sinister."

Tell me about his fortress.

"I worked on that monstrosity for almost a decade, planning and constructing. We used a magical system of gates and controls that Mastaba had personally planned out, to maximize our space."

"I think the most interesting part of that cursed work was the construction of this system. Certain amulets were needed to make it to any of the machinery repair areas."

"The antechamber he devised had some sort of interpreting device that looked for the amulets on a person. Weird room, that antechamber. Full of statues that were too life like to be mearly statues."

These statues, were they alive?

"No the statues were not alive, though they may have been living at one time. Mastaba use to joke that the statues were the victims of his Basilisk figurine in the clock tower."

"I have never seen the likes of this fictitious beast, so I sure can not believe that such a horror exists, but with the likes of Mastaba, this beast is not so fictitious."

Tell me more of this system

"One needed to wear the appropriate amulets before entering this antechamber. The system counted the amulets on your person and in that way it was decided which of the machines rooms you arrived at."

"Though it was an infernal device, I still marvel at the ingenuity of this masterpiece of magical work. A clever method of keeping away the unwanted."

"And now, my power grows weak... I cannot hold this form any longer: I must bid you farewell. Heed my warnings, and do not disturb the forces of Mastaba."

Note: As far as I know, it's not necessary to have this conversation to accomplish Mastaba's related quest(s). This is only a hint.