A guide on how to find and complete the Suma Sahma shrine.
How to Find the Shrine
Go to Wasteland Tower, then go southeast along the mountains. Continue traveling southward on the mountaintops (but stay on the north edge if you want to avoid the Guardian Stalker on the way) to reach Mount Granajh. On top of Mount Granajh, read the diary in the ruined cabin to start the shrine quest.
Then start a fire if you have a source of fire and wait until noon. Pick up a snowball and go south from the cabin to see a shrine pedestal on the wall. Don't jump down from the cliff. Hold the snowball and wait until 4:00. The pedestal will glow orange. Move around so the shadow of the snowball is centered on the circle in the middle of the pedestal. The shrine will appear nearby.
About the Shrine
The chest in the shrine contains a Moonlight Scimitar.