M19 SSM Rocket Launcher

From MLGWiki

The SPNKR "spanker" rocket launcher, both in Halo: CE and Halo 2, has been a staple of the definition of "power weapon". The max ammo capacity is 8 rockets where a pair of rockets are already loaded until being fired then the second one revolves into the firing tube. One direct hit will kill, and splash damage generally disables opponents' shields. The only defense against the rocket launcher is an over shield.