Level 1- Tutorial. Alright soldier, all you need to be in is to pass this test. Level 2- VR. Here's some training for you, before an actual battle. Level 3- Stranded. While on our way to the drop area, some enemies found their way into our ship! Secure the ship. You have us with you to help. Level 4- Stranded to Base. Thanks for securing our ship, soldier. Now we need you to jump out into the enemy base.
That's all I can think of... no, hold on... Level 5- Base. They've sent in reinforcements, but after we left. We'll pick you up afterwards. Level 6- Base to Stranded. It was all fun and games on the way home, but oh no... we found something else! Zombies! An infection has spread through half of us. Help us ward them off.
