DragonForce's 'Through the Fire and Flames' is widely considered to be the hardest song in the Guitar Hero series.

The statement is true because "Through the Fire and Flames" by DragonForce is widely considered to be the hardest song in the Guitar Hero series due to its extremely fast and intricate guitar solos. The song's intense speed and complex patterns present a significant challenge for players, requiring exceptional finger dexterity, precise timing, and a high level of skill to master. Additionally, the song has become iconic in the series, often being referenced as one of the most difficult songs to successfully complete.