M&M's Shell Shocked is a platformer in a similar vein to Crash Bandicoot. Players take control of Yellow and guide him through various sections of the M&M's candy factory, breaking crates and jumping over obstacles. Yellow can defeat some enemies by jumping on them, or by using his spin attack. The game also features a number of driving levels in which Yellow takes control of a car and avoids obstacles as he drives.
Shell Shocked shares a number of features with the older PC game M&M's The Lost Formulas, but without the focus on math and with graphics slightly downgraded to suit the PlayStation.