PM-40 Anvil

A pump-action grenade launcher holding three grenades, and the last launcher to unlock at level 54.

Camos for the PM-40 Anvil

14 camos in order: 8 Military, 3 Special, then Gold, Platinum and Harmonic Break.

Earned by levelling the PM-40 Anvil. Every weapon shares these eight; only the levels differ.

Unique to the PM-40 Anvil. Finish the challenge in either Multiplayer or DMZ.

Night SnowUnconfirmed
Multiplayer Get 10 Direct Shot Kills against Players
DMZ Get 25 Direct Shot Kills against Enemies
RecursiveUnconfirmed
Multiplayer Get 5 Double Kills against Players
DMZ Get 2 Kills without Reloading 20 times against Enemies
Urban StandardUnconfirmed
Multiplayer Destroy 30 Killstreaks or Vehicles
DMZ Get 100 Enemy Kills while moving

Each one opens when the step before it is done.

Gold
Once all 11 camos above are done, get 15 kills in one Multiplayer match or 100 in one DMZ match.
Platinum
Once all 4 launchers have Gold, the launcher challenge is kills without taking damage.
Harmonic Break
Once all 33 weapons have Platinum, the launcher challenge is player kills.
Divergence
Follows automatically after 33 Harmonic Break camos, and opens the mastery camos.