a boy and his blob LYB file

[HoJ]

The wad file contain lots of  .anb, and .lyb file  but i don't know how to open these files.

I think .anb is object image file, and I found sprites character and enemies.

but there is not background images, I think .lyb is background image file.

How to open .lyb file?
or where i find the background images.