As is, there are two tags for this nerd.
Duck_hunt_dog and Mr._Peepers.
It looks like the most common one is the former. I think this is the best option, seeing as it's the most intuitive, widely used, and isn't disputed.
But according to the Wiki page, the only proper name for him is Mr. Peepers. From what I've looked at, the name was only mentioned this Kid Icarus interview, and they later took the name out.
Seeing as how Mr. Peepers is an extremely obscure name, and how the dog (with duck) is just called "Duck Hunt" in game, I'm for aliasing Mr._Peepers to Duck_Hunt_Dog.
Thoughts?
Updated by furrypickle