So I'm working on the "On a Rail" achievement in Minecraft, and I'll tell you: the hardest part isn't gathering a thousand rails, oh no; the hardest part is placing them all down without getting rekt by a bunch of mobs or dive-bombed by a creeper (and yes, that did happen to me). Sometimes, as I was riding my minecart back and forth from my home bed to the growing end point, it was just fun to snipe mobs as I passed by.
And that's where this idea came from.
Let me know what you think of this! I know it's not my best work, but it was a fun idea to work with all the same. ^^