"Sanctum: Collection" from Humble Jumbo Bundle
You will receive a gift URL from Humblebundle like humblebundle.com?key=xyz123
For more information check “How to Redeem a Gifted Bundle or Game” https://support.humblebundle.com/hc/en-us/articles/209021847

For more information about the game take a look on the steam store page (click on the game image or the steam icon above the description)