Mastery
Unlock all Weapon Attachments
500 Kills
Prestige Veteran I
250 Headshots
Prestige Master I
2500 Kills Silver Prestige
Prestige Veteran III
1000 Headshots Gold Prestige Prestige Master III
http://callofduty.wikia.com/wiki/Callsigns
Lots of people do by hacking very few probaly 2 or 3 actually have all titles
By getting into a tenth prestige lobby.
Peronnally I like the M16A4, but you might not agree. Try putting a holographic sight/ red dot sight on it, if you don't like the cold steel. The M16A4 is a headshot killing machine!
yes you do
do some challenges they will unlock it for you ------------------------- Completing every challenge will unlock every title.
There isn't one.
2 ways, you either get them all by completing there various challanges (YaY). or you can do the prestiage hack and get all of them like that (BOO!)
Yep. I have all of them, and I am Prestige 1 and Level 70, except the Prestige 10 title.
Yes you lose everything but titles and emblems
M16a4
They can be found at the Call of Duty wikia. A link has been added under related links