Just reach rank 47.
First of all, perks are upgraded by completing a series of perk challenges. To get a perk uograded to "pro", you have to complete 4 of the perk challenges. So, to get Overkill Pro you must complete the challenge called Overkill Pro IV, which is completed by getting 120 kills with your second primary weapon.
yes, because overkill is perk 2 and the flamethrower is perk 1. so you get 3 weapons
Overkill is the perk that lets you gave two primary weapons.
Yes, the overkill perk was removed; but there are rumors of its reutrn through the Stimulus Package.
you have to have the perk 'overkill' on.
to put what he said in english, get 120 kills
You get 100 or 200 kills with your second primary weapon
U cant, only works on infected matchs etc, where the host doesnt want to give a perk, just doesnt touch the perk icon.
Yes, when playing MW3 and you have a specialist and you unlock a certain perk so many times it does become pro.
Yes you can get it as a secondary weapon but you have to unlock the perk overkill.
Ak-74u Silencer G36c Noob Tube Frag Smoke Perk:1 Whatever Perk:2 Overkill Perk:3 Deep Impact
the best class to use is your favourite smg with silencer and stinger as your secondary and perk 1 sleight of hand perk 2 asassin perk 3 stalker