Today I bought Overgrowth at full price (29.99) from the official page, that lead you to buy it from humble bundle.
Now I see the freedom bundle, you get very good games with it, like stardew valley, subnautica, super meat boy, and other games and books, and one of the games you get in the bundle is Overgrowth, all of this at the cost of 30 dollars.
Thank you very much Humble Bundle.
Well not all is bad, at least I gave the money to Wolfire.
Wathever, great game and sorry for my english.