Very neat! This got at my soft spot for Pico-8 games, but it felt like a simple idea executed really well. The aural & visual feedback from rapid tapping was satisfying & also ensured the player was looking in the right spot to see the effect of their actions on Sisyphus. The expanding glow on the boulder with faster tapping feels almost like a diegetic interface element; like this mystical glow engulfing the boulder from the inside to shove it down the hill. Great work!