Go to VIP and walk north-west to the teleporters. Go up the stairs four times and you will find the teleporter that leads to the Quest. Note: You will need Achievment level 15 to pass the door.
After entering the Teleporter, you will have to go through the door to the south, which requires Level 400+.
You will have to go to the south-east, fighting your way through alot of Furies until you eventually face an Apocalypse.
Kill it and continue your way to the south east until you face a Verminor.
Kill it and follow the way to the east, fighting your way through another Apocalypse and some Furies until you reach a teleporter.
Upon entering the Teleporter you will have to kill a Charizard and then use the cart to the north-west in order to proceed.
Follow the road and go down the stairs, you will find yourself in a small maze protected by alot of furies.
Head to the south-east and step on the throne.
Continue this step four times, until you eventuall get teleported into the middle of the room.
By stepping onto the throne again, you will enter the final room, where you will face the final boss: Aryenai.
After killing it, simply use the cart in order to get to the reward room.