The clown's original picture had its background masked.
Clown Source
The curtain's original picture was masked and was given the multiply blend mode
Curtain
The elephant's orginal picture had its background masked and was given the dissolve blend mode
Elephant
The floor had the other half of the picture masked and was given the multiply blend mode
Floor
The lion had its background masked and was given the darken blend mode
Lion
The trapeze had everything masked but the character
Trapeze