
The Mission
Your Destiny Quest giver wants you to collect the Phoenix of the North, which is part of the Phoenix Medallion.
The first thing that you have to do is to go to the Eiglophian Mountains. There, in the Dinog Village near the entrance, you will speak to a man by the name of Niall. Niall will tell you more about what is going on and send you to go kill Mithrelle in her ice cave.
The Ice Cave
Getting to the actual entrance to the ice cave is a little tricky, but it is not too bad. Once you find it on the eastern end of the map, you need to break the ice covering the entrance in order to go inside.
The first thing that you have to watch out for in here is falling rocks on the path downward. Make sure that you at least have particles turned on and set to yourself. By doing this, you will actually be able to see where the rocks are going to fall. Smoke will rise upward from the spot that rocks are going to fall for two to three seconds before the rocks actually start hitting the ground.
You will see Acheronian Slave mobs standing about or pathing around as you make your way down the snowy hill. It is best to go ahead and kill all of these Slave mobs.
Make your way down the path to the bottom of the hill, where you will see a stone archway. This archway will lead you to Mithrelle...and her worm.
Minions: Ice Worm Hatchlings
Going through the stone arch triggers a cut scene. Once you are inside, you will see a large ice pond with egg sac mounds on it, and above them Mithrelle standing on a ledge overlooking the pond. Behind Mithrelle there is a stone statue protected by a spell shield. This is where you will find your Phoenix of the North.
Once you get close enough to Mithrelle, the fight is triggered. Mithrelle herself does not come down off her ledge, and hitting her does you no good. Those egg sac mounds that you see on the ice will begin to spawn Ice Worm Hatchling minions. You can handle these in one of two ways: Kill the minions as quickly as possible each time a mound spawns a new set of minions or kill the egg sac mounds as quickly as possible to prevent the minions from spawning. You may see some minions doing this method, but you will not get overwhelmed by them, either. Once all of the minions that can spawn have done whether you let them all spawn or kill egg sacs), head toward Mithrelle to get her to unleash her beast: The Dominated Ice Worm.
Boss: Mithrelle And The Dominated Ice Worm
When the Ice Worm boss is unleashed, Mithrelle teleports herself to the middle of the ice pond. The Dominated Ice Worm is an easy thing to kill, but there are two ways to handle it.
Ice Worm Method 1: This is the easiest of the two methods, as you will only need to deal with the Ice Worm and can ignore Mithrelle for the time being. Just kill it. It's health goes down pretty fast, even when Mithrelle loses control of it (you will see a prompt on your screen stating Mithrelle lost control of the worm). With the Ice Worm dead, you can deal with Mithrelle by herself (a much safer proposition than the other method).
Ice Worm Method 2: The second way to deal with the worm is to start beating on it until you see a prompt on the screen that states Mithrelle has lost control of the ice worm. At this point, stop what you are doing because the ice worm will start to attack her. If you continue attacking the ice worm, it will go back to you, instead. While the ice worm is attacking Mithrelle, you should be attacking Mithrelle, too. When she regains control of the worm, go back to hitting the worm.
Dealing with Mithrelle: No matter which method you choose to use in dealing with the Ice Worm, there are a couple of things you need to know about Mithrelle. First, if the ice worm is alive you will not damage her unless it is attacking her and she has lost control of it. Second, no matter which method you choose you will be knocked back by Mithrelle at certain intervals. Immediately after being knocked back, Mithrelle is automatically stunned. You should use this time wisely to hit her with everything that you've got to do as much damage as possible. It is said that, after the ice worm is dead, you can break line of sight from Mithrelle until she has attacked five times -- at which time you should run in and attack her with everything that you have.
The Phoenix Of The North
Once Mithrelle is dead, go up on the ledge behind where she was standing. You will notice that the spell shield protecting the stone statue is gone. Collect the Phoenix of the North from this place and return to your Destiny Quest giver.
The quest is not quite over once you have spoken to your Destiny Quest giver, however. You must go to Old Tarantia to speak with Kalanthes. You are told that you will find Kalanthes behind a blue door. This blue door is located near the Traders in the city. Speaking to Kalanthes ends this quest.
Your next Destiny Quest begins at level 60.