here is a real life example. not a toy or a video game...
The weapon looks like a big portable cannon, and creates a neat looking smoke trail to help locate campers.
Railguns are the future of how nuclear weapons can be launched. Nuclear missiles usually undergo 4 phases, some of which have problems....but with a railgun, there are less required phases, and it's apparently inexpensive! And that's not even the scariest thing.....you know how nuclear missiles are shot down? It's because nuclear missiles burn propellant, and interception technology can pinpoint it, and shoot down the incoming nuke with ease....however, with a railgun, the missile doesn't have to burn any propellant, and therefore it is INVISIBLE!!
Thus, railguns are capable of launching nuclear missiles that can be considered "invisible nuclear missiles"....the thought of that is VERY frightening. And yet, strategic and effective.