Gyromite's companion release constitutes the only other game ever officially designed for R.O.B.... and, frankly, we'd all have been better off if R.O.B.'s library had begun and ended with Gyromite. Seemingly rushed to production (the game evidently hit Japanese store shelves a mere month after completion), Stack-Up makes poor use of R.O.B, of the NES, and of players' time and money. At least the music is catchy.