Successfully complete the indoor shooting range with a "S" or better rank to unlock the "Real-time Window" option at the "EX Options" menu.
Successfully complete all EX missions to unlock the "Professional Mode" option at the "EX Options" menu.
Successfully complete all EX missions to unlock the "Continuous Mission Mode" option at the "EX Options" menu.
Shoot about five or more people in the head.
To easily kill a Boss, shoot them in the head.
In Silent Scope EX, you will encounter a helicopter Boss. He will have an afro and a teddy bear in the front seat. Shoot the teddy bear in the head and the helicopter will crash.
After completing all the levels there will be a final confrontation level. You will have to get to a swordsman Boss and defeat him. He will come at you with his sword. Shoot him then. After that, you will have to find your way to a 1-shot Boss. To kill him easily, wait for the shuttle to stop moving, then make your shot. After that, you will have to kill your own Boss.