One of the important things in CoM:Z2 is currency. Currency in CoM:Z2 are vouchers, tCrystals, and cash.
In CoM:Z2, currency can do many things.
Vouchers: Vouchers can hire characters, upgrade their stats, and upgrade their ability!
tCrystals: You can use tCrystals to buy weapons, fill insufficent funds, playing Hard mode on Daily Missions, use the Daily Luck Machine again, or try to switch the items in the Daily Luck Machine.
Cash: Cash is the most common type of currency in CoM:Z2. Cash is used to buy weapons, upgrade their stats, and buy ammo.
How to Get CoM:Z2 Currency
This will teach you how to earn CoM:Z2 currency.
tCrystals: Buying it, getting it from the Daily Luck Machine, or being MVP on Boss Raid
Cash: Trading it from tCrystals, doing Daily Missions, doing Boss Raid, getting it from the Daily Luck Machine, or by doing Days.
Vouchers: Trading it from tCrystals, getting it from the Daily Luck Machine, doing Days, or doing Daily Missions.