Henkan Chōriki Ohranger

Henkan Chōriki Ohranger is the currently nonexistent Sentai off of which Power Rangers: Neo Zeo is "based." It is not technically abandoned, but up for adoption to any interested writer.

Synopsis
In 1999, a trio of inexperienced U.A.O.H. recruits are transported to a parallel reality in which the Machine Empire Baranoia won. With the help of a lone, slightly crazy survivor, they get to work saving this new world from its robotic overlords.