This is "hey psst, wanna buy some cubes" by Tomislav Jagnjić. Not only does the work itself conjure up a whole world in the viewer's mind, but the irreverent title gives it a whole new meaning. It's not some giant monster everyone fears. No, it's just the neighbourhood cube dealer.
Jagnjić's work is getting noticed now for the truly epically named "yo bro is it safe down there in the woods? yeah man it's cool." He commented on the sudden popularity on Facebook:
And as much as that title is truly a masterpiece, there is also "nope. wrong way, turn around":
And "How do you mean you don't wanna go outside?":
(I think the answer is pretty clear: there are giant leaf people outside. That's how I don't wanna.)