This Tomb Raider is not like the old series. This one is more like Uncharted to me where you explore areas, find collectables, perform a certain level of freerunning, solve area puzzles, shoot stuff, etc. It would be like if Uncharted met Far Cry in a way in that you can hunt animals as well. Now, I haven't completed it, but I did play a few hours and it was an enjoyable experience well worth the price of admission.
how does humble bundle work (never used it). Isnt it only for PC?
Humble Bundle gives you games dependent on the payment conditions. For example, for the lowest tier you have to give $1 in order to get Steam keys. For the following tiers, there will usually be a "beat the average to get" which will tell you the current average payment. For that, you just have to give at least a penny more and you get those games as well on top of the initial batch. Beyond that, like with this one, they may have a specific price tier that rewards all of the games from that tier and lower. Basically, the more you pay the more you get in these Humble Bundles with it still being far cheaper than buying each game separately.
Other than that, it is entirely PC. If DRM free versions are available, you get those, and as I mentioned, as long as you give at least $1, you get Steam keys for the games as well.