Lost Boy Cavern is situated directly north-northwest of Lake Canulus, in the Nibenay Valley and east of the Silverfish River. The entrance to the cave is embedded in a moderately sized rock. Notice that it is a necromancer cave due to the Nightshade and skull-sticks.
Summary
Lost Boy Entrance
When you enter the cave, you should immediately find a burning corpse- nothing on it. Continue searching around and looting chests; many will contain moderately powerful magical equipment or items. In the first level of the cave (Lost Boy Entrance), you should find two more entrances: the Lost Boy Yawning Halls and the Lost Boy Canyon.
Lost Boy Yawning Halls
Several necromancers and other enemies can be found in this level. Some of the necromancers are holding moderately powerful magic items, such as scrolls and potions. Occasionally, they will wear armor of some sort. Continue looting throughout the cave. Noteworthy are the a couple notes found in the cave, which entail rituals and information on necromancers. Once you have gone throughout this cave, continue to the Lost Boy Hidden Bastion.
Lost Boy Canyon
Nothing too noteworthy here except for a one or two chests containing weak magic items, and necromancers. Although another Hidden Boy note is found here.
Lost Boy Hidden Bastion
Search throughout the third level of the cave (overall easier to navigate). A desk with a red tapestry above it contains some interesting notes. Read the three Angry Letters to the Mages Guild. Each letter describes a lich named Erandur-Vangaril.
On the desk is also some alchemical tools useful to you. Afterwards, go towards the stairs near the desk and walk straight up, and continue until you enter a room with two sleeping slabs, and a stairway blocked by dirt with a chest under it. Kill the necromancers in the room, and continue towards the chest near the stairs. Inside the chest is a key and another note. Pick them both up, and search around the room for more chests.
Head back down the stairs and enter the "Old Wooden Door" with an average lock; the key will open it. Inside the room you will encounter two Skeleton Guardians and Erandur-Vangaril, a necromancer turned lich. Take the gaurdians out, but Vangaril won't attack, nor can you attack him, unless you're at least level 23 when you first enter the area. Head behind the chair and there is a chest with a note upon it. Read the note if you wish. The chest has an 'average' lock level and cannot be opened with the key. Inside the chest is another note, and a level-dependent treasure.
Enemies
Unique Enemies
- Erandur-Vangaril (Present but "ghosted" until the player reaches level 23)
Plants
- Cairn Bolete
- Wisp Stalks