He can lead you to training in all Skills and Powers (except Shadow Magic and Weaponry:Lances). See Adventurer Collective.
He can also converse with you about a variety of topics. Since most of the topics of interest are related to quests, almost all of the following should be spoiler-commented.
General stuff Edit
- Thane Pyrond
|Ildraria OR Jagged Iron Shard|
|Cave of Four Spirits|
Once you have Tzal-Toalth visit the Guildmaster in the Adventurer's Collective. Converse with him about 'Tzal-toalth'. This will open the location The Cave of Four Spirits in The Withered Hills, where you get the first gem for the staff.
After you get the gem from the cave and buy the other one from Mezaryl, return to the Cave of Four Spirits to find a strange egg.
After the egg has hatched, the creature inside the egg will have disappeared and you will be given the word 'Thulwy'. Visit the Guildmaster in the Adventurer's Collective and converse with him about Thulwy. This location will appear in Western Tysa - The Edgelands, under Trithik Nearby Locations.
Return after completing Thulwy and say it to him again for a 1024xp bonus!
|Hall of Seven Ghouls|
The FIRST time you defeat all seven of the ghouls, the ghost of Lord Creyn will give you a Hideous Spider Statue - ask the Guildmaster about Lord Creyn for a bonus of 8 AT and 1,024 exp.