ONE PUNCH! (Three! Two! One! Kill shot!) I'm here! Victory assured! Total invincibility! What'd you say? Frustration! I NEVER STOP.

The 1080p opening is praised for its dynamic sakuga (high-quality animation), featuring Saitama destroying massive monsters with single, devastating blows while the environment disintegrates around them.

The song highlights Saitama's status as a "hero for fun" who doesn't seek fame or applause, despite being the strongest being alive.

Released in late 2015, the opening quickly became iconic for its high-octane rock energy and fluid animation by Studio Madhouse. It serves as a high-intensity contrast to Saitama's often mundane and bored lifestyle, emphasizing the raw power he possesses but rarely gets to fully utilize.