If Nerf rifles could look any more badass than it already does, then it'd look a lot like the Steampunk Big Daddy Gun by Etsy designer 'faustus70.'
The designer has taken the N-Strike Barricade Nerf model and has remade it into the dangerously looking Steampunk Big Daddy Gun. He customized the item with wooden planks from an old chair and wrapped it around the toy to give it an organic look. The earthy aesthetic is then accented by aluminum, which has been riveted onto the wood for support. The top has an access panel just in case the darts get stuck. There's also a scope at the top for those who like shooting with accuracy.
There's only one Steampunk Big Daddy Gun available. So if you want want, I suggest placing an order as soon as possible.