a.k.a. Downsize
Binary Arts, circa 2000.
(plastic box, 12 pieces, 40 problem cards, 4.25 by 1.5 inches)

The board has 13 spots on which pieces can be initially placed. The goal is to remove all but one of the pieces by hopping them off (hopping over a piece removes it). Downsize is the same puzzle with the same cards, but different graphics. The 40 puzzles cards, rated from beginner to expert, including problems where the position of the final piece is specified. For example, here is the front and back of Card 40:

The 40 Hopper Puzzle Card Problems