The Hammer Spree is a spree medal awarded in Halo 3: ODST and Halo: Reach for killing five opponents in a row with a Gravity Hammer or 7 wood without dying. Unlike the Sniper Spree and the Open Season medals, you can use both RT and B to get kills towards this medal, and to ultimately save ammo. In Halo: Reach, the announcer won't shout it right away, similar to Killing Frenzy from Halo 3.