Complex sentence: This display again featured concepts from the Disneyland Haunted Mansion, but it also displayed concepts, props, and costume pieces from the 2003 film "The Haunted Mansion" which was based on the attraction.
Split into simpler sentences: This display again featured concepts from the Disneyland Haunted Mansion. But it also displayed concepts from the 2003 film, "The Haunted Mansion", again based on the attraction.