Fists of Fury
Fists of Fury is an achievement in Halo: The Master Chief Collection. It is unlocked by beating the 8,000 point par score on the level Regret. The achievement is worth 10 gamerpoints. Though it can theoretically be unlocked on any difficulty, more points are awarded in campaign scoring when playing on higher difficulties.
The name of the achievement is a reference to the fact that the player must kill Regret by pummeling him to death.