Silent Scope 2: Dark Silhouette

Double Hit Bonus:
To get a "Double Hit Bonus" just fire right when a moving tagets walks behind a stationary one or when two moving targets pass each other and they line up in one in front of the other (relative to you).

Exchange a Half of Life for 5 Seconds:
Pause gameplay and press Up, Up, Down, Down, Left, Right, Left, Right, X, Circle.

Exchange 5 Seconds for Half of Life:
Pause gameplay and press Circle, X, Right, Left, Right, Left, Down, Down, Up, Up.