There's no shortage on creative fans of all franchises doing amazing things with Lego, and next in line is the person behind the ZaziNombies account on YouTube. He has built two pretty amazing replicas of Reapers oh-so-very-deadly Hellfire shotguns from the game, and even has Lego ammunition to go with it.
Roughly 1,100 pieces went in to the construction of these things, which has a weight of half a kilo. They even shoot darts, which probably won't do a whole lot of damage, but sure is very impressive to us. Take a look at this thing over here - there's even a nifty Reaper mask (also in Lego) for maximum effect. Have you created anything cool in Lego?