Put the block down the hole without rolling it off the platform. Bloxorz sounds easy enough, but unless you've got some exceptional spatial relations skills, it won't be too long before you encounter a truly mystifying scenario. And it'll hurt, because you'll know that there's a solution, and probably a deceptively simple one at that.
I usually throw in the towel pretty early with these types of games. There's something about Bloxors' tactile controls and slick presentation that keeps me persevering far longer than I normally would, though. And I like that I can always use a passcode to return to the last level I've played.
Big thanks to ijed for submitting Bloxorz. If you'd like to suggest a game for Act Casual, drop us a line at firstname.lastname@example.org