I have a house that is 15 years old and the tile in the bath rooms are loose and not in good shape.
I removed the tile with a large pry bar and hammer. The lewane board was put in place with ring nail and needed to also have the nails removed. The pry bar was driven under the space between the subfloor and the lewane. Bit by bit it came up. A 52sq. ft area took about 5 hours or hard work but it can be done.