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.
AGQ3#-38Y0X-MBAYL ;
Just replace the # with the missing letter.
It's a lovely space arcade with trading cards and Steam achievements. I already have it in my library, so sharing the extra key here, as usual.
May it cheer you up a little :)