The Labyrinth is a new map that pits players against Halloween-themed opponents to get the ultimate prize of Halloween-themed goodies. The main draw of the Labyrinth would be the intense farm one can do to get, mostly, Halloween drops like Candy Corn, Trick-or-Treat Bags or Large Candy Bags. Typically the best way to absorb this content is to follow the massive Commander-led Zerg to hit all the big Legends as well as the Candy Corn nodes.
Best skills to have on hand in here would be condition cleanse and movement abilities so that you can keep up with the Zerg and take on the Legends without worrying too much about the conditions they drop.
How To Get In
To get into the Labyrinth (and thereby getting to the Clocktower) you will want to head to Queensdale, Kessex Hills or Gendarran Fields. In these maps you will find door icons (called Mad King Door or Bloody Prince Door) that you can interact with. With enough interactions you will eventually find a door which stays open and allows you to travel to the Mad Realm.
Grand High Viscount of Candy Corn
One badass Candy Corn elemental that will drop a nasty AoE ranged attack that will generally drop most players if not watchful.
The best strategy for this is fight is to prepare projectile reflection/negation skills and get right in his face.
Occasionally a candy field will spawn (typically under his feet if everyone is in melee) which will grant you stacks of a "Candy Coated" buff. This buff can be argued for good and bad, as it does seem to grant a damage bonus but at the cost of hitting a Candy Crash for some detrimental debuffs.
Will spawn a Magnificent Chest nearby where it spawns, and can be opened once a day.
Legendary Skeletal Lich
A nasty skeleton which will summon large amounts of minions, a massive AoE life steal and use a fear and torment combo.
Best strategy here will be to stay at range and put your back to some wall or obstacle. The range will help you avoid the minions and AoE, and getting into a position where you can't run away (due to the fear) will mitigate a lot of the torment damage.
Will spawn a Magnificent Chest nearby it's spawn point, inside of the small building.
Roaming skeletal jerk what will switch between single target destruction to AoE torment madness. Appears to have the least amount of health out of the Legends.
The best strategy I can come up with is to hammer on immobilization to this guy so that he doesn't constantly swap targets after dropping a player. His AoE Torment ability is a pain to telegraph, but there is a point where he starts to live his sword up that you can dodge.
Interesting part to this Legend is that he will spawn anywhere on the map around a player. Because of this you will generally have the Horror jump in on the other Legend fights for one heck of an amusing time.