Two factions of Mahjarrat
Speak to Ali the Wise in Nardah. He will start a discussion on the two factions of Mahjarrat, those who support the god Zamorak, and the god Zaros. He asks your opinion on the two factions, and which one you feel is the greater threat.
Ali the Wise will give you a digsite pendant which will allow you to teleport to the Digsite Exam Centre. After he will send you to speak with Dr. Nabanik at the Digsite Exam Centre.
Talk to Dr. Nabanik, and find out that he is really Azzandra in disguise.
He'll ask you to help him get a restoration certificate for the altar below the digsite, however, the people around the Digsite don't trust him, so he'll need your help in gaining their trust.
Talk to the expert in the building and make up a history that shows Azzanadra to be wealthy, and knowledgeable. (Most seem to work). He will give you restoration certificate. Take this to Azzanadra.
Restoring the Temple
He requests you to go to the altar, using the winch to the north-west of the digsite.
He will give you a rope to use. Use the rope on the winch, and then operate the winch. Head into the temple and talk to Azzanadra.
He sends you on two tasks: one in the wilderness; one in Morytania.
The Barrows Icon - First Task
Azzandra sends you to the Barrows to find an icon that absorbs prayer. The 6 Barrows brothers were left by Zaros to forever guard this icon. Your goal is to go in, defeat all 6 brothers, and raid the chest. Once you raid the chest, you will be rewarded with the Barrows Icon.
Take the icon to Azzanadra.
The Frostenhorn - Second Task
Azzandra's second task is for you to find the Frostenhorn, located in a frozen fortress in the North. This task is very dangerous, however, as the last person Azzandra sent returned without being able to retrieve to the horn. Read the letter Azzandra gives you, and you will find out that the person had to leave because of the lack of proper runes. Azzandra will then tell you that his adventurer would never be caught short without combat runes, so another type of rune is needed.
Prepare for combat. You will need an antifire shield, a weapon with armor, food, a few prayer potions, a hammer, and the runes for needed for telekinetic-grab. Head north through the wilderness until you reach level 51, on the western side, making sure to bring the Heat globe Azzandra gives you. Right along the mountain border, you will find a pedestal. Place your first heat globe in the pedestal, and squeeze by the melting ball of snow. Run fast into the castle, as the Steel Dragons guarding it are not happy with your intrusion! The castle entrance is on the south side.
Head up the first set of stairs, and then east and down the next set. Next to the door, find the holes in the wall and scale the wall.
Up stairs, East, down stairs, scale up wall. Notice the broken pedestal, as it will play an important part later. Walk west, scale down the wall, and head into the underground section of the fortress.
Warning: As you melt these ice blocks, you will release waterfiends. You can kill them or avoid them, but they will re-spawn.
Go east, and grab the first heat stone (number 1), and place it at the pedestal to the west next to the blocked doorway (number 2). Walk through the doorway, telegrab the stone, and place it on the pedestal (number 3). Head down the trap door.
Head south, and grab the stone off the pedestal (number 4). Place it on the pedastal to the north (number 5). Go east, and grab the imperfect stone off the pedestal (number 6). Head back to the above-ground part of the castle, and find the broken pedastal again. Place the imperfect stone on the top of the broken pedestal (the part on the ground), and roll the pedastal down the snow pile.
Head back to the second underground level. Follow the path to the southeastern room (number 7) and grab the heat stone. Place the stone in the pipe (number 8) and hit it with the hammer. Head up the southern ladder (number 9).
Once upstairs, prepare for combat. The Ice Demon you are about to fight has a powerful magic attack, and weaker melee attack, so turn on Protect from Magic. The Ice Demon will drop the Frostenhorn.
Teleport back to the digsite, and give the horn to Azzandra. He wants you to collect relic from someone outside the temple. Head back up the winch, and collect the artifact from the assassin. Take the relic to Azzandra, and watch the cutscene. Zaros' communication portal is restored! Quest complete!