ideas: a upgrade that increase the percentage off how many containers you receive (ex. if you get normaly 1 and you have 100 procent of the upgrade, you will receive 2)
an upgrade that you receive more money when you kill a ufo
and now i go Always to level 600,700,.. and it takes a lot of time to get to there if it is possible that you get non stop ufo and not you kill 10 you get the other 10, no just everything come together
 "Transport Defender"){kind=icon}