The Humble Monthly Bundle is a $12 subscription service that instantly gives you access to one game, and then a whole bunch more a few weeks later. Last month the featured game was Stellaris, while this time around its Dark Souls 2: Scholar of the First Sin Edition which includes all of the DLC.
A lot of people consider Dark Souls 2 to be the weakest part of the Dark Souls trilogy, and I can't say I disagree with them, but then again the weakest part of the Dark Souls trilogy is still one of the best games I've ever played. So if you have even an inkling of interest in action-RPGs, and you don't mind a bit of challenge, I would heartily recommend you give Dark Souls 2 a try because for $12 you are getting an absolute ton of gameplay.
Just keep in mind that you only have one more day to grab it before the Humble Monthly Bundle rolls over to the next game, so try not to laze around lest you forget and miss the offer entirely. Also, don't forget to unsubscribe if you're not a fan of next month's featured game! There is no rush given that you will only be billed halfway through the month, but as before, its better to be safe than sorry. Have fun, and try not to die!