At the end of finishing the main story, you try to finish the challenges like what I did. At some point you can barely kill the enemies which forces you to grind to get better weapons which require you to level up which require you to make a custom game just to grind to beat the challenges. This happens in all three games, it's frustrating how we have to go into an endless cycle just to accomplish one simple mission and then go into the endless cycle again to complete the next and repeat.
 "OutHack"){kind=icon}
 "Strike Force Heroes"){kind=icon}
 "Strike Force Heroes 3"){kind=icon}
 "Crush Crush"){kind=icon}
 "Strike Force Heroes 2"){kind=icon}
 "Sherlock Has a Clue"){kind=icon}
 "Stealth Hunter 2"){kind=icon}
 "The Last Stand: Union City"){kind=icon}
 "Deadswitch 2"){kind=icon}