Goosebumps Gold
These books appeared on series illustrator Tim Jacobus's website and marketing sites but were never released. In this series, Stine intended to write a sequel to The Haunted Mask (mini-series) (The Haunted Mask Lives!), a sequel to Welcome to Dead House (Happy Holidays from Dead House). It was one of the two book series by R. L. Stine that were planned to be released at the same time in 2000 (the other was The Nightmare Room).
Read more about this topic: List Of Goosebumps Books