Nick0GR wrote:
After you survive the first 10 rounds you get a chance to exfil(basically evacuate), if you chose not to then you have to wait for another 5 rounds so the exfil slots are something like 10,15,20,25,30,35,40, etc. This was mainly done for people that don't want to go for crazy high rounds and so they gave those people the option to leave early but still get a little extra reward. You have some easy to obtain permanent upgrades in the form of skills that you upgrade using aetherium crystals and exfiling gives you extra crystals and XP depending on the round that you chose to do so. Also, exfiling isn't as simple as pressing a button, you need to kill a certain amount of zombies in a certain time limit or the helicopter is shot down.
shot down by what lol? zombies have guns now?