Right now the newest one is WB Games Bundle. With many repeats, but if you miss some of those games, it's great. And it's one of the strongest 1$ tiers ever.
$1
– Scribblenauts Unlimited (great for children, adults will probably get bored after 1-2h, but the overall idea is phenomenal)
– Middle-earth: Shadow of Mordor Game of the Year Edition (for 1$ it's a steal, everyone should know that one)
– Batman: Arkham Origins (called "the worst" Batman from the Arkham series, but in no means a bad game)
BTA
– Bastion (GREAT little gem)
– Mad Max (the one I don't have, can't help you with that!)
– Injustice: Gods Among Us Ultimate Edition (good fighting game, actual nice story mode)
– 10% off LEGO The Incredibles
$12
– Batman: Arkham Knight
– Batman: Arkham Knight Season Pass
– $2 Humble Wallet credit for Monthly Subscribers