1
get 50 knife kills
If you have not prestiged then you do but if you have you get to keep the prestige veteran and master kill numers
tactical knife on a pistol. You can get it by getting I think 50 kills with that certain pistol.
15 kills with a silencer
MasteryUnlock all Weapon Attachments500 KillsPrestige Veteran I250 HeadshotsPrestige Master I2500 Kills Silver PrestigePrestige Veteran III1000 Headshots Gold Prestige Prestige Master III
camp
482
the m93 raffica
Some say it isn't possible, but I think if you have the Final Stand deathstreak and the Last Stand perk enabled, and you are very very good with a pistol, that you can achieve that.
get enough kills to get to level 70
you have to get 250 kills with melee
Well if you are a sniper about 30 but if you run and gun its about 50 to 7