Beat Blocks make their debut in Super Mario Galaxy 2, appearing exclusively in the Beat Block Galaxy. In this appearance, all Beat Blocks are cube-shaped, and alternate between yellow and green. Mario or Luigi must traverse this galaxy, which is made up almost entirely of Beat Blocks, with caution and good timing. When the effects of the Double Time Comet arrive, the Star mission "Silver Stars in Double Time" causes the Beat Blocks to alternate at four times their regular speed (despite the mission's name).