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.
0X896-ZEXK7-V#9I8 ;
Just replace the # with the missing letter. Please note also that the key may not be activated if you already have any of the Gothic games on your Steam account.
(Actually that's why I'm giving this key here)
Enjoy! :)