Due to the above-ground troops' persistent offensive strike, the Lastabad main forces have hidden themselves from the above-ground forces and slowly reassembled into 'Lastabad'. Now, from the reported 'Diad Fortress' base, the above-ground leaders have reports of the Lastabad's route to a giant underground great cavern.
1. Through magic and secret paths, located behind the Diad Fortress is the giant Underground Great Cavern. To the northwest is the Resist region (including a village), to the southwest is the Recluse region (including a village), and there is also the Grave of Ancient Giants (to the southeast and northeast).
2. The Underground Great Cavern is a new area and may be reached through the Earth-Depths Lake.
Use of the Diad Fortress has been divided into two types: when PC's [players] occupy Diad Fortress and when NPC's occupy Diad Fortress. When PC's [players] occupy the castle, the castle doors are opened and the 'Great Cavern Teleporter' inside the Diad Fortress may be used to teleport, but when the NPC's occupy the castle, one must use the 'Great Cavern Teleportation Scroll' to teleport. (Both will teleport to the Resist region of the Great Cavern.)
3. The Lastabad dark elves drop 'Great Cavern Scroll Piece' and 'Diad scroll Piece'. The 'Great Cavern Scroll Piece' is used to craft the 'Great Cavern Teleportation scroll' and the 'Diad Scroll Piece' is used to craft the 'Diad Teleportation Scroll'.
The NPC who crafts these scrolls is 'Consul' and is located at the entrance to the 1st floor of the Lastabad dungeon.
Because you are teleported to the location of the 'Aden Scout Patrol' when using the Diad Teleportation Scroll, use of the scroll will make moving to the approximate location of Diad Fortress easier.
4. There are two alchemists in the Underground Great Cavern.
1) Alchemist of the Resist Region - can craft the Scroll of Return - Resist Village, Lesser Healing Potion, Healing Potion, and Greater Healing Potion. Located within the Resist Village's town.
2) Alchemist of the Recluse Region - can craft the Scroll of Return - Recluse Village, Potion of Bravery, Potion of Wisdom, and Elven Wafer. Located in the Great Cavern's eastern area.
5. In the Grave of the Ancient Giants, the powerful Grave Guardians appear. Located in the southeast area of the Grave of the Ancient Giants is the NPC "Kalbas' Hein" who can craft the "Alchemist's Stone".
Also, in this location exists a route that connects with the 'Demon Temple'.
Thanks to Wae's LineageCenter for the translation.