In multiplayer, Marines will find that it's a good tactic to stand back-to-back and 
be ready for anything. One should cover the floor, with the other watching the ceiling. 

Take your time as the Predator. Use your blaster on the Aliens; the spear gun and 
shoulder launcher are ideal for killing humans. 

When playing as the Alien, rush your victims while keeping the action key depressed. 
You'll slice and dice like a Cuisinart.