Bone Cracker

From Halopedia, the Halo wiki

Template:Ratings

Awarded after you kill an opponent by meleeing them in Multiplayer.

The Bone Cracker (or Beat Down in Halo 3) Medal is awarded for hitting and killing an opponent with a melee attack that isn't an actual assassination (melee attack from behind). It is available in all Multiplayer gametypes and has a Bungie difficulty rating of 3 (out of 10). It is represented by an inverted silver star with a dark green fist. After you kill an opponent with a melee attack, a message appears on your screen that says: "You beat down (player's name)". It is also awarded if a Covenant Energy Sword or Gravity Hammer is used to kill an opponent from the front.

The Green Fist

The "Green Fist" could be a reference to the Incredible Hulk, the Hulk using it's fists a lot and the fact they're both green.