I only got two hint's so far and I will add more.
1. You can hit people through walls because your hammer will appear like its hitting the other person on the other side of a wall.
2. ALWAYS TAKE COVER because theres a 1 in 10 chance your gonna hit some one with a gun if you run head first at them.
3. Be careful because if your on teams you might hit your partner.(It's a no-no

)
4. Will make you walk slower.