Tomb location: Argolis, the northern part of the location.
Enter the tomb. On the left-hand side of the room, you will find a pathway that will take you to another room. Inside, you will find a blocked passage. In order to unlock it, hit it. This way, you will be able to get to the other side.
Continue, and then turn left. Go downstairs. You will reach a room with a puzzle.
You have to move the shelf towards the wooden stakes blocking the pathway. When moving the shelf, watch out for multiple traps set out in the room.
After you place the shelf in the right place jump onto it and them over the stakes.
In the next room, you will find a chest that hides the Ancient King’s Helmet. It is a regular item, though – if you have legendary armor, this helmet is not worth your attention.
Continue to reach a room with a board. You complete this tomb by activating it. On the left-hand side of the room, you will find a passage to another location. Inside, you will find another chest hiding the Heavy Bow.