Unlock the following bonuses by performing the corresponding tasks:
HOW TO UNLOCK
After you finish the main Campaign and buy the Advance Campaign, hold down the Select button before entering Campaign Mode and you'll play in Advanced Mode. You'll face stronger enemy opposition, but win more coins if you complete the mission
Open Up New Gameplay Modes
To open up the War Room, Campaign, Design Maps, and Stats options on the main menu, you must first complete the final mission in Field Training.
To access the field training mission called Special Intel, first you must clear all of the other Field Training missions. When you go back to field training you'll see it in the list of missions.
Unlock CO Drake
You must select Andy for these missions during campaign mode: Captain Drake - Naval Clash- Wings of Victory - Battle Mystery.
Unlock CO Eagle
Choose Sami for Captain Drake, Naval Clash, Wings of Victory, Battle Mystery - At the end of the campaign, you will have a final battle, between Andy (you) and Eagle
Unlock CO Grit
You must select Max for Mission 4 in Campaign mode and complete the campaign. Grit will then appear in the Battle Maps section to be purchased for 50 coins.
Unlock CO Kanbei
You must complete the Campaign. He will appear in the Battle Maps section to be purchased for 50 coins.
Unlock CO Nell
Once you have purchased all of the CO's and completed Advanced Campaign, Nell can then be bought in the battle maps section for 80 war coins
Unlock CO Olaf
Successfully complete the Campaign Mode.
Unlock CO Sonja
Unlock and win Sonja's secret missions in the campaign (see other hints) and complete the campaign. Sonja will appear in the Battle Maps area to purchase for 60 coins.
Unlock CO Sturm
Once you have purchased all of the CO's except Nell from Battle Maps (Grit, Eagle, Drake, Kenbei, and Sonja), Sturm will appear on the list and can be purchased for 100 coins. Note - Sturm can only be used in Vs. mode.
Use other CO's in multiplayer
To use other CO's in multiplayer, you first beat campaign and then go to battle maps where you can buy them.
When you defeat a country's factory but lack the money to buy any COs or maps, simply restart the campaign. Once you restart you'll still have your early COs and maps, allowing you to replay the campaign and do all the easy missions to get points.