Well it depends. If you like using assault rifles I would use the Scar-L and the FMG-9. With Scavenger pro. Hardline and Sitrep pro. ANd killstreaks, The Osprey gunner, The pavelow and a UAV. Equipment Claymore and Flash. Or ACR with the same perks and equpment. If you like Sub Machine guns you should use, UMP45 with focus and a P99. Equpiment Bouncing Betty and Concussion Grenade. Pers Sleight of Hand, QUickdraw, and sitrep. Killstreaks, UAV recon drone and Juggernaut. If you like Sniping, you should use L118A with MP9.Equipment, B-Betty and Concussion Grenade.Killstreak, Whatever you want. Perks, Sleight of Hand, Quickdraw, and Marksman. Light MG's you should use M60E4 with MP9. KIllstreak Juggernaut, Pavelow and UAV. Equip. Claymore or Semtex. Perks, Sleight of Hand, Marksman, and Sitrep. These are what I would approve it you want to be on a killing spree.