Survivor's "Eye of the Tiger" opens with one of the most immediately recognisable guitar riffs in hard rock history, built on a four-chord progression — Cm, Bb, Ab, Bb — that cycles with a clenched, muscular insistence. The movement from the root minor chord down through the flattened seventh and sixth degrees before lifting back to that Bb creates a sense of coiled tension releasing and re-tightening, neither fully despairing nor triumphant, but driven and purposeful. For guitarists, the progression sits naturally under the fingers in the lower register, lending it a physical momentum that feels almost inevitable. Released in 1982, the track became a defining moment for the punchy, arena-ready hard rock sound of that era.