Password: FRGT
Shoot the red switch on the left with Baleog's arrow to stop the rotating shaft and switch off the electric fence. Then move left and fall down with all vikings, jumping for the two bombs with Erik at the top left. Carefully pass the electric fences. Use a bomb on the floor at the right. Then fall down with Olaf to protect, and kill the electric enemy. Then proceed to the teleport with all wikings.
Glide through the pit using Olaf's shield (don't fall down yet!), and jump across with Baleog to land on top of Olaf's shield. Shoot the switch on the right, and proceed to the teleport on the left with Baleog. Jump down the pit with Olaf (avoid the two electric fences), then jump across the room collecting the red key. Press the red switch at the bottom right to switch off the electric fence below, and proceed to the teleport.
Now time for Erik - jump across the pit to the teleport at the top. This takes him below where Olaf was collecting the red key. Jump across the electric bridge, and release the bomb mid-jump in the air to destroy the floor blocks under the fence. Proceed to the teleport. In the new room, jump across the teleport to collect the bomb, and jump down to the left. If you arrive at the elevator field at the right speed/angle, he will easily fall down. Use bomb on computer at the bottom. Then go back up, and fall down on the right side (electric fence now defunct).
Once you're down at the bottom with Erik, pay attention very carefully, as this is a hard part. You'll have to avoid fire balls, so be careful with timing. Pass to the left, then go up. In the second floor, there are fire balls and electric fences, and the yellow key. (Note - the yellow key sometimes didn't appear for me, maybe a bug?) Then go on to the right. Now pay attention very carefully, as there's electric fence at the top right! So you'll have to immediately pass to the left as the elevator field lifts you up, and dodge the fireballs, otherwise you're dead. After you're on the left side on the 3rd level, steer towards left to avoid hitting the electric fence.
[To be continued...]