These hyper-exotic plastic firearms by Mattel aren’t just kids’ toys. They’re also toys for grown-up kids, thank you very much. As anyone who plays a fair amount of videogames can vouch, it’s only natural to develop a fetish for wickedly exaggerated weapons of destruction that are far too impractical to exist in real-life.  That is, unless they are produced as toys that fire darts, like these magnificent creatures in the BOOMCo line, coming this summer, just in time for that family reunion where you can pass it off as quality family time. Looking at these magnificent creatures, you can clearly…