Misty Quagmire

The Misty Quagmire is an area only obtainable after you get to a certain point in Marquis Teodoro Jr.'s quest. After you reach this point, you will be able to ask him about the Misty Quagmire, and he will take you there. It is not accessible from anywhere else.

You will find yourself in an unknown area. The marquis will ask you to hurry up and do your thing. Using the Witcher's Eye, you will view scenes from the past.

A mound of dirt will appear and you can dig it up to gain the bone leg.

A second mound of dirt will appear and you can dig it up to gain the Charred Vampire Shoe.

After you have viewed all the scenes, talk to the marquis and you can leave.

NOTE: There is currently a glitch where you may get stuck in the Misty Quagmire¹ and the clouds may disappear. The only known way to fix this is to leave and re-enter the game. It is recommended that you save the game before entering. It may be possible to open your universal bags and rearrange your inventory to make sure the Witcher's Eye is in your main inventory to have the clouds reappear.

¹ If you are in possession of the Universal bag make sure, you have enough space in your main inventory for the bone leg and the Charred Vampire Shoe. The Marquis_Teodoro_Jr won't let you leave, if one or both of the items are in your Universal bag.