How do I go down the northern staircase?

Hint 1 of 5:

If you head north, you'll fall down the stairs to your demise.

Hint 2 of 5:

Grappling down would help the situation much.

Hint 3 of 5:

You should have a rope, right?

Hint 4 of 5:

Tie the rope to the altar.

Hint 5 of 5:

Take the rope, and throw it north.