from the introduction: The World of Zendynn is a supplement for the Millenniums & Mutations game that provides a map of the known world, along with 300 creatures and 100 robots to use in designing your adventures in this post-apocalyptic world. There are versions of Zendynn that is dependent on the version of Tunnels & Trolls you are using. from the footnotes: Creatures for Zendynn are from the Post-Apocalyptic Fantasy Role-Playing Game Broken Urthe converted for use with Millenniums & Mutations. User comment: This version of the setting book has statistics compatible with Tunnels & Trolls (7th - 7.5 Editions). There is an alternate edition with statistics for Tunnels & Trolls (5th - 5.5 Edition).