First, get Jax's Rocket Launcher in Shao Kahn's Tomb. There are 12 interactive Krypt objects, and the rocket launcher is the 11th. You will need all the other objects to access it. Just carefully explore the Krypt, and one object will lead to the next. You do not have to spend money on any of the unlocks to obtain the objects. While inside Shao Kahn's Tomb, you must activate three levers to open a large door. Behind this door is the rocket launcher. Then, go to the Shrine Of The Dead at -11, 12 coordinates, and use Jax's Rocket Launcher to enter it. Go to -11, 13 coordinates, and gamble your koins in order to unlock the Kamidogu and win other items in the process. To obtain the Kamidogu, you must gamble at least 10,000 koins. Use the Kamidogu to gain access to the NetherRealm (where the final few unlockables of the Krypt are located) through the Nether Gate at -24, 18 coordinates.