DD

D.D. (Diamond Dog) was the pet canid of the private military company Diamond Dogs during the 1980s. Like his owner, Venom Snake, the dog wore an eyepatch over his missing right eye.

Biography
As a puppy, D.D. lost the use of his right eye. The puppy was found alone by Venom Snake during a mission, sometime after the latter's recovery from a coma in 1984. D.D. was later taken by Fulton Recovery to Diamond Dogs' Mother Base, his new home.

The puppy was present with Ocelot upon Snake's return to Mother Base, licking the latter's face as he picked him up. Ocelot explained that the puppy had been a troublemaker after it had arrived, and that he was unsure of its specific breed. Believing that the pup may be useful in the future, Ocelot intended to train him, comparing him to a diamond in the rough that required some polishing. Snake agreed, noting the irony of an ocelot raising hounds.

After D.D. had fully grown and been trained for a combat support role, Big Boss had the dog accompany him on his missions, at the suggestion of Ocelot.

Behind the scenes
D.D. is a character that appears in Metal Gear Solid V: The Phantom Pain. D.D., or at least, the concept of a dog acting as a partner for Big Boss in missions in a new Metal Gear game was first hinted at in the GDC 2012 website Development Without Borders, which included a "secret" concept art depicting Big Boss with a dog. This artwork was later updated to better reflect the game's development. D.D. made his debut in the TGS 2014 demo, more specifically the showing on September 19/September 20. According to at least one source, when D.D is first recruited, the iDroid notification refers to him as Wild Puppy. D.D.'s exact breed is unknown as he has described as being a wolf, a dog, or a wolf dog (hybridization of a domestic dog and a wolf).

Like Quiet, D.D. will accompany Snake on missions via the buddy system, and also like Quiet, meeting him will be entirely optional. During the demo unveiling how the player can find D.D., Big Boss throws an Active Decoy that piques the pup's curiosity. In the Japanese version, the decoy balloon that popped up was of Lisa, the ghost from the P.T. demo of the cancelled Silent Hills. The English version had a variant of Big Boss's standard one.

One of the journalists who had early access of The Phantom Pain implied that D.D. could be rescued as early as the Afghanistan missions.

On May 27, 2015, Hideo Kojima tweeted two photos of a prototype D.D. figure by Play Arts KAI wearing a Sneaking Suit while holding a knife in his mouth. The latter aspect is most likely a reference to the FOXHOUND logo. On the June 17 demo for Metal Gear Solid V: The Phantom Pain at E3 2015, some elements of D.D.'s role as a buddy combatant was shown. D.D.'s gender was confirmed to be male in the main menu featured in the demonstration, with the presenter repeatedly referring to him by masculine pronouns, and supported by D.D. lifting his leg up to urinate at the start of the mission (female canines squat when urinating).

When first encountering the puppy, Snake may also encounter it's parent, who will attack Snake after fultoning D.D. The player can also fulton the presumed parent, but this has no effect on the storyline.

Potential encounter locations
Once Mission 02 has been cleared, D.D. can be found near the deployment points of Missions 03, 04 and 05. The main points he appears in during free roam are near Shago Village, the Eastern Communications Post and Wakh Sind Barracks. If Mission 02 is replayed, he can be found on a hill before the first guard outpost.

Tranquilizing the puppy is optional but not necessary. He can be recovered via Fulton when he is found.

In the TGS 2014 Demo, the puppy will be found near a dead wolf whimpering (the wolf is implied to be its parent, with Sean Eyestone implying that the wolf had been killed by a sniper round heard earlier in the game) before discovering Snake in Africa. However, in the final version, as noted above, it can be found in Afghanistan, and its presumed parent is not only alive, but can even attack the player shortly afterward. The demo also implied that D.D. is found after fully recruiting Quiet as a buddy character, but the final game makes clear that DD is found well before Quiet is fought in a boss battle, let alone recruited as a buddy character.

Gameplay
Photos released in June 2015 show that D.D. can be told to sit in the passenger seat of a jeep. The photos came from the Official PlayStation Magazine and Official Xbox Magazine, which also confirmed that D.D., when acting as a partner, will sniff out guards and herbs, bark to warn of any enemies, objectives, animals, weapons, and hostages nearby, as well as attack enemies at the players command, as well as confirmed the Play Arts KAI figure's implication that he could be dressed up in clothing. It also confirmed that if the player misses D.D. in the mission he is recruited at, he will never be recruited. The demo confirmed most of the above, and also revealed he could distract any soldiers to get Snake out of a tight spot by barking. The presenter also mentioned that D.D. will occasionally urinate and mark territory. D.D. can be outfitted with fultons and can extract prisioners and enemies when ordered to. He have unlimited fultons and will extract all enemies/prisioners he can see.

When D.D.'s relationship has been maxed out, the player has the option to customize D.D.'s eye and coat color.