Plus One (1980)

"Plus One, the 4-sided electronic computer, remembers every flip, every flop. You and your opponent alternately tumble Plus One down an invisible path on the gameboard by adding one move every turn. The course... of course... gets longer and more difficult with every turn! Listen to Plus One's guiding tones and watch its color caps for clues. But stray from the path and Plus One gives you the "razz"... you've lost! Plus One is the 4-sided electronic computer with the one-track mind. Give it a tumble for unforgettable fun!" It's very much like a board game version of Simon in which you move a pyramid shaped electronic device around a triangular board.