The original operators required for this are:
Sledge, Thatcher, Ash, Thermite, Twitch, Montagne, Glaz, Fuze, Blitz and IQ
Smoke, Mute, Castle, Pulse, Doc, Rook, Kapkan, Tachanka, Jager and Bandit
The renown needed to unlock all these operators is 1000 renown. The fastest way to make the renown is to play multiplayer it can net anywhere from 200 - 450 depending on score/kills and doesn't have a renown cap per day like the other modes.