The '100% Full Combo' (FC) meme originates from the dedicated rhythm gaming communities of the mid-2000s, where players recorded themselves hitting every single note in songs from Guitar Hero and Rock Band. These videos, often featuring incredibly difficult tracks like 'Through the Fire and Flames,' became symbols of extreme skill and perseverance. In modern meme culture, the 100% FC overlay is used to signify total mastery over a situation, intense focus, or the sheer adrenaline of completing a difficult task without a single mistake. It serves as both a nostalgic nod to classic gaming and a universal signifier for achieving perfection under pressure.