A third game in the 7th Guest series, a sequel to The 7th Guest and The 11th Hour, has been in development for many years. Legend Entertainment developed a prototype of real-time 3D game called The 13th Soul with the Unreal Engine in 1998, but the project was canceled. Work was halted with the closure of Trilobyte after being evicted from its office in 1999.
In 2003, co-creator Rob Landeros posted a design document for The 7th Guest Part III: The Collector on his personal web site. Lunny Interactive released a promotional video of the game that was based in a German museum. It was set to be released in 2004, but was scrapped.
Trilobyte, relaunched by Landeros, has since been seeking crowdfunding for the project. A Kickstarter campaign failed to raise $435,000 in 2013. A more modest Crowdtilt campaign in 2014 failed to raise $65,000 to build the first floor of Stauf's mansion, where the current version of proposed game is set.
Another Kickstarter campaign succeeded in raising $60,266 for a fan game called The 13th Doll. The original target date of August 2015 has since been pushed back to Halloween 2017.