Unimplemented and Unfinished Content

Dark Majesty Quest and Undead Story Arc
In an interview with Warcry, Stormwaltz shared the overall design for a major quest that didn't make the cut for Dark Majesty. From Asherons Call: 4 Years of AC and Counting, Part 2 - L'etoile, Part 2:

Remnants of this quest still exist. The most notable are The Great Machines found in the damns on Marae Lassel, which were to play a key role in this quest. Some of the Tall Tree utterances make reference to this quest. The Ossuary found in the East Fork Dam Hive may also be related. Finally, the Asheron's Call Dark Majesty: Sybex Official Strategies and Secrets contained the stats for numerous creatures which never appeared in the final release of Dark Majesty, among these creatures was Emperor Geraine I (possibly a typo as in the official lore he is Geraine IV). The Undead Story arc would later appear, slightly modified, in Asheron's Call 2.

Eastern Island
In the original version of the game, there was a large island to the east of Dereth, beyond Asheron's Island.

Fifth Sending of Darkness Live Events
In an interview with Warcry, Stormwaltz mentioned some ideas that were scrapped from the first story arc. From Asherons Call: 4 Years of AC and Counting, Part 2 - L'etoile, Part 2:

Frozen Wasteland Island
From Taste of Twilight: Stormwaltz Comments on the Aerlinthe Quest: {{Turbine Developer | Date = July 29, 2000 | Link = None | Text = I'd also like to take a moment to note that the “frozen wasteland” island was not supposed to be open for play for some time yet, and it is only reachable through a bug. It is still in a very early stage of construction, as evidenced by the extreme performance hit in the ice gardens - the degrade art for those beautiful ice upwellings has not been completed, so everyone on the screen is rendering at full detail, no matter how far from it you are. There are no plans to open the ice island anytime in the near future, although its construction began at the same time Aerlinthe's was. The landscapes of the new islands were designed by artists Pete “Obsidian Span” McDonald, Sean “Shadow Spire” Turbitt, and Bil “End of Beta Comet” Mauritsen. - ChrisL (Stormwaltz} | Developer = Chris "Stormwaltz" L'Etoile }}

Rennaj
The Rennaj were a planned 4th heritage group. On Turbine's Beta page Sketches, there was an image with the file name rennajcity.gif, which in the image was labeled Rennaj City.

This was later referenced in a dev chat.

This developer chat, which occurred in June of 2000, may have been the inspiration for the Floating City Quest, which was added in October of 2000.

Tumerok War Spear
During The Changing of the Ways event, a new interaction was added to the Exploration Society Letters quest. After turning in a stamped letter, players would receive the Exploration Society Token. The NPCs would direct you to bring this token to Bach Lien, in the Explorer Society Outpost on the road between Rithwic and Dryreach. Unfortunately, no such NPC or outpost existed. Turbine confirmed this was a bug:

This was later reiterated in the Flesh and Blood State of the Code:

This quest may have been the inspiration for the Tumerok Banners Quest or the Aun Tanua's War Taiaha Quest.

Witch Cave
We know little about this quest other than the name, and that it probably wouldn't have meshed well with the overall continuity. The only mention of it is from Stormwaltz Quotes: On Harlune and the Storyline: