Hint: Bunch up your players into one large group and kill your enemies in one
fell swoop.

Hint: Make sure the right guy picks up the right power-up. It would be useless
for a guy with a crossbow to pick up bullets; he wouldn't be able to use them.


Hint: Blow up barrels to find hidden items.
                                        
Hint: Invest in guns and ammo early on so you can take out enemies more easily.