Feel free to correct me if I'm wrong, but I think this is the first time RPS have presented detailed instructions on how to build a concealable assassination tool. Given that I'm writing on a website that Kieron Gillen is a director of, I find that baffling. Anyway, how many fingers do you have? All of them? Would you like one less? You'll need a drawer, a screen door, a throwing knife, and balls the size of a baby's head.
Ok, look: don't try this. Please. Just watch the video, be amazed and then do what I do and place a plastic ruler in your sleeves and make a “shunk” sound with your hand. If you do decide to make it, please turn it into an automatic banana dispenser, or a way of keeping your house key easily to hand. If there's a spate of “Idiot Skewers Brain While Picking His Nose” headlines over the weekend, you'll make me very sad.
Now you just need to learn to run across rooftops and you're sorted.