North Sea Icy Palace Dungeon:

 

First Room:

Once you have put the 3 pass you start in the main room and there is a poison in the dungeon. There is a lot of time to do the dungeon.

Map of the room :

1. Go in the room [1] and defeat all the mobs there.

The mini boss : Sealed Soul Infantry has a para skill.
2. Then go in the room [2] and defeat all the mobs there.

The mini boss : Red Soul Palace Guard has a Bleed and slow skill.
Keep going in the big room and enter in the other small room.

3. Go in the room [3] and defeat all the mobs there.

The mini boss : Icy Palace Attitude has bleed skill.
4. Go in the room [4] and defeat all the mobs there.

The mini boss : Sealed Soul Patrol got slow skill.
Once you have defeat enough mob the poison is off : (If you haven't killed enough with the 4 room go back to the main room and kill the mobs.

Once the poison is off, you have to defeat a boss at the end of the main room. His name is Cursed Frozen Captain.

5. Once the boss is dead the doors are open and you can go in the second room.

 

Second Room:
Map of the room :

1. You have to defeat the mini boss in 2 of the room at the right of the corridor.
Go in the first room at the right [1] and defeat the mini boss there.

2 Icy Palace Javelin and Sealed Soul Guard Leader which has Bleed and slow skill.
2. Go in the third room at the right [2] and defeat the mini boss there.

Same than previous room.
3. Then the middle room is unlocked [3] , go inside and defeat the mini boss.

Those mini boss have para and speed decrease skills. Once those are defeated you will be able to open the doors in the room
If you have done the following quests :

The Secret of the North Sea Former Matriarch (I)

The Secret of the North Sea Former Matriarch (II)

The Secret of the North Sea Former Matriarch (III)

You will be able to use the door at the right of the room :

This door will lead you to the NPC for icy palace special collection.

See at the end of the gudie for all the details.
Go back to the previous room. Then use the doors at the left of the room.

This path will lead you to the boss room.

Boss Room:
Map of the room :

1. In this simple room you will find different kind of mobs.

Once you have defeat enough mobs, the boss will spawn:

2. Defeat first the Boss : Fallen First Princess.

3. Then attack the Fallen Second Princess, this boss has 2 forms :

Now you can defeat the boss North Sea Queen in peace :
She has 2 form and use some skills :
- -50 all Stats
- Silence Skill
- Stun AOE with some damage.

 

Once the boss is dead you can enter in the loot room. Then exit by the doors. 

 

-Collection NPC:
For those collection you need the following collectibles :

 

The relics :
You need 12 Stone of Icy Tears and 240 Pure Ice :

You need 10 Stone of Icy Tears and 200 Pure Ice :