Classified Employment Contracts (CEC) are a type of currency in COUNTER:SIDE used specifically for the recruitment of Awakened units. If you’ve played E7, the system is analogous to mythic summons and moonlight heroes.
1. Event - get more rewards
2. Main - to open upper contents
3. Side Story - until you get all side only characters
4. Supply - when you did all 1~3 but you have Eterniums left (check more details below)