What is the term for a roller coaster that is built on or spins inversely to its original design?

The appropriate term for a roller coaster that is built on or spins inversely to its original design is a twisted coaster. Twisted coasters incorporate elements that create a complex track layout, often including multiple inversions, sharp turns, and unique structural designs that deviate from traditional straight paths. This twisting design enhances the thrill and excitement by adding unexpected elements and changing directions, providing a dynamic experience for riders.

While looping coasters primarily feature vertical loops and inversions, and spinning coasters involve cars that turn independently, twisted coasters are distinguished by their intricate, often unpredictable paths that twist around themselves. Reverse coasters, on the other hand, typically refer more to the direction in which the train travels, rather than an innovative design concept based on twisting. Thus, the characteristics of a twisted coaster make it the accurate choice for this question.