Unlockables Free Play:

Acquire Tutorial Map:
Finish all tutorial levels

Campaign & Mission Maps:
Finish the corresponding Campaign or Mission Battle

Type 61 SP and Type 74 SP1 (Japan):
Finish Campaign Level 2: "Graduation"

MBT Type 69 and WZ551 (China):
Finish Mission 2 in Mission Mode

Leopard 2A6 (Germany):
Finish Mission 3 in Mission Mode

F35B (America):
Finish Mission 4 in Mission Mode