If a wave is generated in a Slinky and the wave hits a wall, the reflected wave will be

If a wave is generated in a Slinky and the wave hits a wall, the reflected wave will be "Inverted".

Explanation:

Three basic things can happen when wave strick the boundary like reflection, diffraction and energy loss. Wave inversion occurs when a traveling wave reflected back into the old medium and flipped upside down. During the process of a wave moving through one medium, this happens to encounter a boundary between that medium and another media. Rigid waves face inversion.

The reflection quantity is determined by the difference between the new Medium properties and the old medium properties. The bigger the difference the bigger the reflection.