Swapping 3D models is usually one of the first mods folks figure out for games without official mod tools, letting you earnestly play as different characters or just dick about and make things weird. Well, folks have been fiddling with Metal Gear Solid V: The Phantom Pain [official site] and sure, you could make it so Quiet takes Snake’s place.
Or you could swap D-Dog for Quiet, making some of the sniper’s already-odd cutscenes get really weird. It’s a simple thing and entirely predictable but, like physics ragdolls freakouts and missing faces, I will always laugh at model swaps gone wrong. Look, this dog thinks he’s people (sorry, I don’t have a better source for that):