The HRM-9 is a submachine gun available in Call of Duty: Warzone.
The gunsmith contains a wealth of different attachments that are capable of transforming the HRM-9 to suit any style of play. After some testing, this set of five is currently setting the meta alight:
This particular build is all about fast reaction times. The Thorn-90 Barrel, Hatchet Light Stock, XTEN Phantom-5 Handstop, and Tac Handler Grip all enhance sprint-to-fire, aim-down sight, and movement speed to maximise the incredible mobility of the HRM-9.
To tame the recoil, the Purifier Muzzle Brake S makes all the difference in those hectic close-range battles where accuracy is the key to evading the NVG Gulag.