Reeshan

Difficulty:  60+ to survive with a sizeable group of at least one full fellowship
Level Restriction:  60+
Timer:  21 Days
Can be Solo'd?  No
Rewards:  Random selection of Experience, Salvage, Portal Devices, or Noble Armor imbue gems 

Step 1 - Preparation.  Like the other 6 kings, you will need at least a full fellowship to try this quest.  You will also be questing for over an hour, so come prepared.  This quest starts at Izji Qo's temple (AKA Blackmire 5), so you should gather your team at a mansion or at the portal drop, which is safe.  When you are ready to start, buff frost weapons, bane physicals and acid, and protect everything.  As soon as everyone is done buffing, run into the temple, jump down the hole, and greet the Watcher of the Dead.  He will talk to you and then teleport you into the dungeon, which is safe.

Step 2 - The Maze.  Each king quest has a section like this one.  When everyone is inside the dungeon, jump down and head to the east, where you will find a ramp.  Go up it, open the door, and make your way ahead, killing as you go.  Many quest leaders prefer to run through these sections, but due to the number of people and monsters, the likelihood of losing a lot of people is high.  Killing is much safer.  Follow the path and you will come to a pair of lever doors, both of which go to the same place.  Pick one, open it, and kill the Burun in the large room.  There are two levers inside - hit them and move to the doors at the NW and SW end of the room.  Both go to the same place, so again, just pick one.  Keep fighting to the west and open the lever door in front of you.  Fight through the next large room and head to the SW.  Open the door and fight through the next corridor to another lever door.  Open it, fight through another room, open the door and run down the ramp.  You will now fight through a large room with a lot of Burun.  While everyone else is fighting, head to the west and find the lever door.  There is a pressure plate in front of it, so step on it, run through and hit the lever.  Run back out and to the SW, where a door will have opened.  Get your team through the door, up the ramp, and then make your way back to the north.  Fight up the ramps and hit the button to open the last lever door.  Once everyone is inside, use the Portal Device in the middle of the room.  You will be teleported to the Puzzle section.

Step 3 - Marbles.  This quest's puzzle is a fun one - figure out which marble goes into which bag.  As you enter, greet the sign to the right of the room.  It will give you 3 marbles - black, white, and mixed.  The object of the puzzle is to figure out which marble goes into which bag.  You are told that each of the 3 bags is mislabeled and you are allowed to pull one marble from one bag to help you solve the problem.  To correctly answer the puzzle, pull a marble from the black bag.  If you get a black marble, you can deduce that the black bag is really mixed, the white bag is really black, and the mixed bag is really white.  On the other hand, if you get a white marble, the black bag is really mixed, the white bag is really black, and the mixed bag is really white.  Place the appropriate marble into the correct bag and you will get a completion message in green text.  Head into the portal to the next section.

Step 4 - The Gauntlet.  Despite looking quite confusing, this section is relatively straightforward.  All you need to do is hug the left wall.  As long as you take the left (SE) exit from the first large room, you will make it to the end without trouble.  Kill as you go - the monsters won't take long to kill and your group will remain together.  At the end, you'll find a portal device in a small chamber.  DO NOT go in yet!  You will need to rebuff first, which you will be able to do without interruption.  Same buffs as before, but Archers should buff a frost render AND a Burun-Slaying weapon if they have it.  Before you go in to the portal, give your battle orders.  Make absolutely clear to mages that they CANNOT debuff Reeshan.  He immediately dispels any debuffs and then buffs himself with the appropriate spell, increasing the necessary time to kill him by a lot!  Also, drop your fellowships at this point.  Reeshan casts fellowship debuff spells that reduce your health, stamina, and mana by half.  If you aren't in a fellowship, you are far less likely to be debuffed.  Melees will be responsible for killing the spawns while archers and mages will target the King.  Archers should set their speed/accuracy slider all the way to the left (full speed), as the kings have 0 missile defense.  Mages should use Frost Wall spells if possible.  It is also likely that the Mages and Archers will be swallowed by the king.  In that event, whoever is swallowed needs to move to one side of the stomach, switch to UA, and start beating on the stomach wall.  When you are ready, use the portal.

Step 5 - Reeshan.  Reeshan has a lot of health, so the fight will take about 20 minutes, even if you don't debuff him at all.  Periodically remind mages not to debuff him, just to be safe.  Reeshan has a nasty habit of casting very potent debuffs on you, including spells that give you the equivalent of vitae or reduce your stats by 99%.  Sometimes, he even dispels you.  In the event you are debuffed by any of these spells, break off your attack, use a dispel gem or rebuff yourself.  Reeshan also casts Blood Loather on anyone who does enough damage, which is why you should have more than one weapon available.  When Reeshan dies, numerous pieces of his hide will spawn on the floor.  Everyone needs to grab one.  The hides respawn about every 5 minutes or so, in the event there aren't enough on the floor initially.  Wait until everyone has their hides - it's possible that people are stuck in Reeshan's stomach when he dies, so make sure they escape before everyone leaves.  When everyone is safe and has their hide, summon Subway and direct everyone to head to Cragstone.

Step 6 - Rewards.  Head to Cragstone and find Guard Ellyon at 25.7N, 48.8E.  Greet him and you will receive one of the possible rewards:

Gem of Perfect Health - for use in Noble armor, granting a +12 endurance cantrip

Black Spawn Den Portal Device - a device that, when hooked at a mansion, teleports the user to one of the 3 Black Spawn Dens

15,000,000 XP

A Bag of w10 Steel

A Bag of w10 Imperial Topaz

A Bag of w10 Fire Opal

You can either give Ellyon your hide in exchange for the title "Reeshan Killer" or you can hang on to it, combine it with the other 5 hides, and turn it in for the title 'Kingslayer' and a hookable Kukuur Float, a decoration for your home.