5.1 Kherab's third quest and the reward
When your PC has done the first two quests for Kherab, the dwarven artificer in Darkforge, he tells your character to "be patient, more will have to be done soon". However, he will never assign the third quest, even to experience level 50 characters who are ready to close the chaos gate or attempt an ultra ending. From scanning the executable, reference to a "spear of raw steel" has been found, seemingly a third quest reward along with the amulet of raw steel and shield of raw steel now available.
5.2 The Scroll of Omnipotence
In the secret compartment of the High Mountain Village, there's a message that reads:
"Dear Lubaf, I am sorry to disappoint you but you won't be able to find the Scroll of Omnipotence in this place. I have hidden it more effectively. You will need to find the red rooster at dawn. Then you'll encounter the final challenge.
With passionate hate,
Alhacrast, Overlord of Jak-Nagiur."
This may be what Khelavaster refers to as the foolish legends that built up around the quest for the crumpled scroll and the Trident of the Red Rooster.
5.3 The Red Rooster Inn
The Red Rooster Inn is mentioned in the executable and is probably a red herring. It was thought in earlier versions of ADOM that the innkeeper would produce the Trident of the Red Rooster in the Red Rooster Inn at dawn.
5.4 The Volcano
There is a volcano mentioned in the executable, but no character has ever found such a location. It may be a remnant left over from earlier development of ADOM, possibly designed to be the location where the Chaos Orb of Elemental Fire could be found prior to implementation of the Tower of Eternal Flames.
5.5 The Weird Tome
The Ghost Librarian in the Library of Niltrias demands silence. In practice, this means the PC must spend a certain amount of time in the Library without speaking. Spellcasting is allowed. After spending 2000 turns (well spent reading spellbooks) without speaking, upon 'C'hatting with him, he gives the PC the weird tome. He instructs the PC to deliver it to the Mad Minstrel, who will in turn reward the PC with five cursed scrolls of chaos resistance.
The mystery about the book is the fact that nobody has managed to read it.
See section 2.22.2.1 for more details about the Ghost Librarian and the weird tome.