Mission One
Scorpion has the Sacred Map and is located past the room with the rope. He can be beat with freezes and combos and finished off with the spine rip. The way out of the mission is down the rope and then down the angled rope.
Mission Two/Three
The keys of Wind and Earth must be found in the next two missions. Fujuin in Mission Two can be beat with freeze attacks at an upward angle. The tablet behind the Earth God in Three contains the secret to defeating him.
Mission Four/Five
The keys of Water and Fire are in Missions Four and Five. Freeze attacks do major damage against the Water God in Mission Four, while fire attacks are needed against the Fire God.
Mission Six
The monks are replaced in the Prison of Souls by guards with cannon-arms. The guard with the saw blade can be beaten with the game controller's "HK" button. The way out is to topple the statue in that same room with the Urn of Strength's help.
Mission Seven
The Bridge Keepers block Sub-Zero's way across the Bridge of Immortality to the fortress. Jump kicks work against the first Keeper, the "HK" button attacks work with the second, and all of Sub-Zero's resources are needed against the third.
Mission Eight
Sub-Zero needs the crystals from the warriors Kia, Sareena and Jattaka to work the elevators. Quan Chi's teleporter takes him to face Quan Chi, followed by Shinnok. Shinnok can be beaten by taking his amulet while he is frozen.