Wolves are wild canid predators that are presumed to be related to the more domestic dogs owned by humans. They are considered noble but dangerous creatures. Unlike domesticated dogs or wolf dogs, pure wolves generally don't bark often. They also don't wag their tails to indicate happiness.
Behind the scenes[]
Wolves appear in Metal Gear Solid V: The Phantom Pain. They can be encountered in Afghanistan, acting as a threat to the player. They first appeared briefly in the Gamescom 2014 demo build for the game, where Snake turns around and sees them shortly after knocking out a sheep and Fultoning it, with the presenter implying that the wolves were about to ambush and kill the sheep when Snake intervened. A wolf also appeared in the rainforests of Africa as the deceased parent for DD in the TGS 2014 gameplay demo, although in the final version, they are exclusive to Afghanistan. Like most large wildlife, it is possible to Fulton extract them if tranquilized or stunned from afar.

A wolf pack featured in the Gamescom 2014 demo for MGSV: The Phantom Pain.
If a wolf pounces the player, the player needs to shake them off. Successfully doing so will leave them stunned long enough to allow the player to Fulton them. When being fultoned, they will whimper slightly before, if the player uses a regular fulton, making a howl.
Wolfdogs appeared in Metal Gear Solid (as well as its remake, Metal Gear Solid: The Twin Snakes) and Act 4 of Metal Gear Solid 4: Guns of the Patriots as a recurring threat in the caves and on the Snowfield, respectively. When killing a wolf in the latter game and using the Codec afterward, Rosemary will warn Snake that he ought to undergo a psychiatric evaluation after the mission due to killing animals indicating criminal behavior, and Otacon will simply make a disgusted groan rather than making any comment due to unpleasant memories of Sniper Wolf's death.
Two wolves appears inside the internal cover art flap for the Metal Gear Solid Original Video Game Soundtrack, as an indirect reference to Sniper Wolf.