The Homunculus

Difficulty:  50+ to survive, 60+ or 70+ to wield the finished Orb
Level Restriction:  None 
Timer:  Unknown
Can be Solo'd?  Yes
Rewards:  Head of the Homunculus house item or Head of the Homunculus Orb

Poor Mosswarts!  The Burun have driven them from their homes and killed a great many of them.  Some have had enough and decided to worship the Homunculus, a dark Idol.  Kill these Enthralled Mosswarts and steal a gem to their hidden lair.

Step 1:  The Search.  The only way to find the Homunculus is to kill lots and lots of Enthralled Idolators or Zealots, who very rarely drop a portal gem.  You can find lots of these guys inside the Lair of the Homunculus itself or you can hunt the East Dires Swamps.  This part of the quest can take a very long time, so good luck!

Step 2:  Lair of the Homunculus.  When you have your gem, you are ready to start the quest.  Gather a group and find a nice flat place to use your gem.  Buff up before you use the gem - you won't really need banes, but make sure you protect against everything.  When your group is ready, use the gem.  Once everyone is in the dungeon, move to a hole in the ground near the drop point.  Your main goal in this dungeon is to make your way down, which will involve several short jumps.  At the base of the hole, you'll find 4 paths.  Pick any of them - they all lead to the same place.  The corridors all lead down stairwells and in to a larger room with 4 ramps leading down toward another hole.  Jump down the hole.  You will again find yourself in the middle of a fourway intersection.  Pick any direction and make your way outward to the NE, NW, SE, or SW.  All paths will lead to a large room with two small spurs leading away from the entry point of the room.  These spurs have openings where you can jump down to the next level.  Hop down and move inward (in the opposite direction you originally came) and you will quickly find another opening.  Hop down and you will be on the last level of the dungeon.  This floor is a simple clover leaf design.  Move to the center of the leaf and you will find a large open room with lots of Mosswarts and the Homunculus itself.  The Homunculus drops one head per kill, so you will have to kill him repeatedly for everyone to get their trophy.  Fortunately, the Homunculus is on a very quick spawn and will respawn almost as quickly as you can kill him.  Once everyone has their head, portal recall out.  If you want to get another gem, this final floor is a good place to loot.

Step 3:  Rewards.  The Head you looted has two uses.  You can do nothing to it and hook it in your house.  Using the hooked head will cast 4 spells on you, raising each of your magic schools by 2 points for an hour.  These spells are fully stackable with other buffs, so it's a great item to have in your home.  Alternatively, you can remove the Head's eyes and replace them with Idol Gems.  If you choose this path, your head will become a spellcasting orb.  Take the head to Grearrk, a Mosswart Emissary in Sawato and he will smash the Head's eyes for you.  Adding the first Idol Gem requires a War Magic check and adding the second Gem requires Item Magic skill.  The Head with Two Eyes is fairly useful (although mostly for buffing), but now can only be wielded by the creator and now has a level requirement.