(Note - Just before the level loads, you have the option of choosing between Drysuit Light or Wet Suit. You can also select your secondary weapon to start with, although you can change it any time from your PDA. Since you begin the level underwater, the Spear Gun would be the best choice for now.)

In the cut scene, following the coordinates that Natla gave her Lara reaches the Arctic Sea. She parks her bike and set an explosion device that blows up the ice, creating a big hole that leads to the ruins. Lara then dives into the water.

Swim down and forward. Soon, you will see some huge statues.

Area overview - There are six huge Norse statues alongside the bridge; three one each side. There is also a tall tower beyond the statues but the drawbridge is up, blocking the way inside. In order to lower the drawbridge, you first have to release the chains that set it in motion and then find four Stones to activate the mechanism that lowers the drawbridge.

As you explore around, you will encounter six sharks in total. You can spend some time in order to kill them before proceeding, or deal with them as they attack one by one. Mjolnir does the job underwater as well, but the shark has to approach until the reticule is red. If the shark swims quite far away and the reticule is grey, you have to throw many energy bolts.

Releasing the chains - Facing the tower and all six statues, swim to the first Norse statue on the left. There is a small alcove behind its head that contains a Health Potion and a wheel (as shown in this screenshot). Approach the wheel and press the Interact button to pull it. This will make the statue to raise its hands, pulling the sword out of the chain.

Swim to the second statue on the left and use the wheel to raise the statue's sword and pull it out of the chain.

The third statue on the left is broken, so there is nothing to use. However, if you approach the depression on top, you will find a Treasure (1/30). (See this screenshot for the location.)

From the statues on the right hand side, the first one has already its sword raised and the second one is broken. So, there is nothing to do there.

Swim to the third statue on the right (the one that is closest to the tower). At this point, the wheel does not work, so swim to the bottom to find two big gears and a Health Potion. The gears glow when you approach them, which means that Lara can grab them. Press the Interact button to grab the first gear and swim to the side of the statue where you will see a gear mechanism and two poles jutting out (as shown in this screenshot). Approach one of the poles and press Interact to put the gear into place. Do the same for the second gear and swim upwards. Enter the alcove behind the statue's head and pull the wheel to activate the mechanism and raise the statue's sword.

Treasure hunting beneath the tower - (This page shows the whole process.) Swim to the part where the drawbridge will lower (between the chains). This is the space between the tower and the broken part of the bridge. Swim down until you see some bones. Opposite the bones is an alcove that contains a Treasure (2/30) and a Health Potion. Once you get them, exit the alcove and turn right. As you swim along the path, keep an eye on the left to spot a Treasure (3/30). Turn around and swim past the alcove and the bones. Soon, you will see another Treasure (4/30) lying on the right hand side.

Searching for the Stones - Swim upwards and turn to face the tower. As you can see, there are two small towers, one on each side of the main tower, with an opening at the bottom. You have to visit both towers in order to find four Stones and it does not matter which one you follow first.

Left hand tower - Before entering the tower, swim down to the lower level and get a Treasure (5/30) from the sand (see this screenshot for the location). Then swim upwards and get the Health Potion in front of the entrance.

Enter the tower to reach the first small room. There is a hallway on the right, but first swim upwards and through the opening above the ladder. When you surface, climb out of the water and turn around. Vault on the low block to the left and jump to grab the narrow ledge. Pull up to hug the wall. Move to the right (Lara's left arm) and jump to grab the beam. Pull up and walk to the other side. Jump to the next beam, then jump to grab the ladder. Climb to the top and press the Jump button to land on the ledge behind.

Break the rounded vase on the right and pick up the Treasure (6/30). Go to the other side and get the Helheim Power Stone #1 from the slightly raised circular platform. Now you have to make your way back, but instead of climbing down the ledges, you can hang from the edge of the opening in the floor and drop to the water below. (This screenshot shows where to hang from.)

Swim down to return back to the small room near the entrance. Do not leave just yet. Swim through the hallway on the left to reach a junction. The way ahead is blocked by rocks, so swim to the right and get the Treasure (7/30) lying on the rock. Turn around and swim forward to the small room with the ladder. Swim upwards to reach the top of the room and turn around. Swim through the hallway ahead to reach a room with many vertical small windows. The Helheim Power Stone #2 is lying on the raised circular platform and you will also find a Treasure (8/30) on the left (as you enter).

Exit to the hallway you came from and halfway through stop and notice the opening above (see this screenshot to get oriented). Swim there and turn around if necessary to spot the Treasure (9/30) on the rock. Then swim through the hallway to reach another room with vertical small windows. Get the Treasure (10/30) and return back to the open sea the same way you came.

Back to the open sea outside the tower - As you exit, swim upwards and to the left to reach the upper level of the main tower. You may encounter a shark, so stay sharp. There are two small stone cones on this level with receptacles at the front. Next to them, you will find the Helheim Power Stone #3 (as shown in this screenshot). Place two of the three Stones you have found until now in their receptacles. You can do it once you find all four, but you will have to backtrack later.

Swim to the front side of the main tower, passing next to another stone cone with a wheel on it. The wheel does not work now, so ignore it and swim past it (as shown in this screenshot). Here you can see two more small stone cones with receptacles at the front. Since you have the third Stone one, put it into place.

Behind the cones you will find a Treasure (11/30). (See this screenshot.) Now swim upwards between the main and right towers. To the side of the main tower is a small room with broken vertical windows (see this screenshot to get oriented). Enter the room and get the Treasure (12/30) from the left. Exit the room and swim down close to the opening of the right hand tower. Swim to the lower level (where the stairs lead down) and around the corner to find one more Treasure (13/30). (See this screenshot for the location).

Right hand tower - Enter the tower and swim upwards to surface. Climb out of the water and break the vase on the right to get a Treasure (14/30). Climb up the ladder and traverse to the narrow ledge on the right. Traverse around the corner and pull up at the end to hug the wall. Jump to the right (Lara's left arm) to grab the next ledge and pull up. Jump to grab the beam and pull up. Walk to the other side and jump to grab the ladder. Climb to the top and press the Jump button to land on the ledge behind.

Grab the next ladder and climb to the top. Jump to grab the beam behind you and pull up. Jump to the next beam and walk towards the wall. Jump up to grab the handhold on the wall and climb to the ledge above. Pick up the Helheim Power Stone #4 and break the vase on the right to get a Treasure (15/30). Turn to face the way you came and approach the left side of the ledge. Jump to the small ledge beyond and break the rounded vase to get one more Treasure (16/30).

Hang from the edge and drop to the beam below. Walk to the other side, hang from the left side and drop to the water below. Make your way back to the open sea.

Back to the open sea - Four sharks are waiting for you as you return back, so deal with them or ignore them (unless they attack). Place the Stone to the receptacle and once you have placed all four Stones, swim to the front side of the main tower and use the wheel.

The cut scene shows the drawbridge to lower, revealing the entrance of the main tower.

Twisted passage - Swim down and through the opening that the drawbridge revealed. What follows is a twisted passage and not a maze, however the diagram on the left shows a simple layout of the passage, mainly indicating the Treasures and the Health Potion.

The passage seems blocked by the rocks, but there is a small opening on the right that you can swim through. Follow the passage and swim through the opening of the next fallen rocks. When you reach the junction, the left way is a dead end. Swim forward, through the opening in the rocks to find a Treasure (17/30). Swim back out and continue to the left. Get the Health Potion from the floor and swim through the opening in the rocks.

On the second junction, turn left (the other two ways are dead ends). Swim through the passage to reach the third junction. The way ahead is blocked by the fallen rocks, so swim to the right and through the opening at the top of the fallen rocks to find one more Treasure (18/30) lying on a rock. Swim back out and continue ahead.

When you reach the fourth junction, turn left and swim through the opening in the top left corner of the fallen rocks. Get the Treasure (19/30) and return back. The right way is blocked by the rocks, so continue ahead and through the next opening of the fallen rocks. As soon as you reach the other side, turn around and look below and to the left to spot the next Treasure (20/30).

Continue through the passage to the fifth junction. First, swim ahead through the opening in the rocks. Get the Treasure (21/30) and return back to the junction. Turn left and follow the passage.

Swim through the opening of the next fallen rocks to reach the sixth juntion. Turn right and swim through the opening in the rocks to find yet another Treasure (22/30). Swim back out and continue straight ahead and through the opening in the rocks. The next staircase leads out of the water.

The cut scene shows Lara entering the next room. As she takes a look around, Natla flies down from above and lands in front of the glowing exit. Lara uses her videocamera and zooms in to take a closer look of what Natla is doing. The latter uses her power and rearranges the lock. She then smiles at Lara, who now has to complete the next part. Natla then flies and leaves the room.

Room with toxic pool - You have to cross the toxic pool and reach the opposite side, but before doing anything, break the rounded vase on the right and pick up the Treasure (23/30). Go to the left side of the ledge and pick up the Health Potion. There is one more rounded vase here with a Treasure (24/30) hidden in it. You may have noticed the symbol that glows when Lara is nearby to the left of the entrance (as shown in this screenshot), but do not bother with it now.

Turn to face the pool and approach the edge. If you take a look below, you will see Yeti and Viking thralls rising from the pool. They cannot reach you up here, however if you stay on the ledge, more of them will keep rising up. So, kill the first group and then drop down to the ledge below. If a remaining thrall attacks, take care of it and prepare to cross the pool.

(Note - If you manage to cross the pool without dying, you will encounter more thralls as you go. On the PC version at least, when a Checkpoint loads, it sometimes causes the thralls not to appear again.)

Crossing the pool - (The entire process is shown in this page.) Hang from the edge and drop to the lower ledge below. Kill any remaining thrall and break the rounded vase to find a Treasure (25/30). Turn around to face the pool and approach the left side. Jump on the metal pipe and walk to the other side. Jump to the small ledge ahead and break the rounded vase to find a Treasure (26/30). There is another symbol that glows on the nearby pillar. Make a note of it because you will be back here later. Jump back to the pipe and return to the ledge where you first dropped down.

Turn to face the pool and approach the right hand edge. Jump on top of the small vertical pillar to perch on it and turn right to face the low wall. Jump to grab it and traverse to the left as much as you can, until Lara is hanging from the corner. Jump to grab the tall vertical pillar behind you and climb to the top. Perch on it and jump to grab the nearby flat ledge. Pull up and pick up the Treasure (27/30).

[Note (Contains SPOILERS) - If you take a look above to the right, you will see a metal ring that you will use in the next part of the level if you want to get the Relic.]

Jump on top of the next tall vertical pillar and climb down to the ledge below. Pick up the Health Potion and break the rounded vase to find a Treasure (28/30). Turn to face the exit and approach the right hand side of the ledge. Jump to the small ledge ahead and pick up the Health Potion. Again, notice the symbol that glows on the pillar, because you will need it later. Jump to the next small ledge where you will find a rounded vase that contains a Treasure (29/30). Jump back to the previous small ledge, then to the ledge with the tall vertical pillar.

Facing the exit, approach the left side of the ledge and jump on the angled pipe. Walk to the other side and jump to grab the edge of the wall. Traverse to the right and pull up. Jump to grab the ledge ahead and pull up. Then approach the exit door.

In the short cut scene, Lara uses Mjolnir to open the door.