faux figurine
A character portrayed standing on a scenic base, similar to that of a figure or scale model. In other words, the base is just a small chunk of ground or scenery on an empty background.
If the background is cropped, but instead of having clear cuts with volume, they appear foggy or as if simply being erased, it's fading border instead.
If the base is large and includes elaborate details, multiple characters, or three-dimensional elements (especially walls), diorama may be more appropriate.
Examples
