Play games
Choose the game that interests you and play itfor free.
Complete the quests
Every game has some quests for which you will receive Soul Gems.
Receive rewards
You can exchange your Soul Gems for Steam Wallet top-ups, game keys, CS:GO Skins and other rewards.
I used to earn SG on the Wall of Terror a lot but one day it stared acting funny and now it's completely broken, I can't seem to access the wall anymore and whenever I attempt to enter it on PC I get directly redirected to the Wall of Darkness . . . anyone with the same problem ?