Complex sentence: Once the monsters are revived they reveal themselves to be the owners of the house and kin to Mr. Morley, Gaspar, Melisandre, and Ludmilla Morley as well as Albert and the were-human Bob.
Split into simpler sentences: Once the monsters are revived they reveal themselves to be the owners of the house and kin to Mr. Morley. They are Gaspar, Melisandre, and Ludmilla Morley as well as Albert and the were-human Bob.