Pay any amount and you get (you must pay a minimum of $1 to receive Steam keys):
- Tesla Effect: A Tex Murphy Adventure
- Always Sometimes Monsters
- Insurgency (One copy for you and three to share!)
Pay more than the average amount and you get the games above and:
- GRID 2
- Euro Truck Simulator 2
- Half Minute Hero: Super Mega Neo Climax Ultimate Boy
- KickBeat Steam Edition
If you pay $12 or more you unlock all of the games above and:
Last but not least, if you share the copies of Insurgency you receive and they are redeemed by December 9th you get a free copy of Full Mojo Rampage.
If you want to check out the bundle and possible purchase it head on over to https://humblebundle.com.
The system requirements for all of the games are available on the humble support site here: https://support.humblebundle.com/hc/en-us/articles/203501460.