|Ground Zeroes Save Transfer Rewards:|
If you played Metal Gear Solid V: Ground Zeroes, you had the option to upload your save file from the main menu. When you play The Phantom Pain, you can download that save, also from the main menu, and you will receive the following rewards:
Metal Gear Solid 1 Skin - Snake looks similar to his appearance in Metal Gear Solid on the original PlayStation.
Ground Zeroes Sneaking Suit - Available as a special upgrade through the Mother Base.
Gold Bionic Arm - Only available if your save was made after you complete Mission 5: Over the Fence and rescue the Bionic Engineer.
* Note that you can also transfer data from the PS3 version of Ground Zeroes to the PS4 version of The Phantom Pain, or from the Xbox 360 version to the Xbox One version.
Kojima Productions Lives:
After you are rescued from your initial encounter with the Man on Fire in the prologue, you must follow someone down a corridor. There's a rail to your left, which lets you pull yourself from the floor. Look closely at the cork board on the wall to see a poster referencing Kojima Productions and inviting you to "Join the Fox Team." There's also a booth number: CP 2308. That booth that was assigned to Kojima Productions during GDC 2013.
The Cake Is For You:
Kojima and team apparently decided it made sense to reward players by letting them have cake. When you start a new game, you'll be prompted to enter your birthday. If you play the game on your birthday, there will be a party waiting for you at the Mother Base, which includes a birthday cake and cigars.
Ground Zeroes - Mother Base Staff:
When you rescue Persons of Interest and Prisoners of War in Metal Gear Solid V: Ground Zeroes, you can save your file from that game's main menu and then download it from the main menu in Metal Gear Solid V: The Phantom Pain for various rewards. The prisoners you rescued will appear at Mother Base as one of your rewards.
Known prisoners include the following:
HIDEO - Diplomat who appears following Missions 3, 4, and 5.
OCHRE CHAMELEON - Appears following Missions 3, 4, and 5.
GRIZZLY HEDGEHOG - Appears following Missions 3, 4, and 5.
HUNGRY CROCODILE - Appears following Missions 3, 4, and 5.
WILD HARRIER - Appears following Missions 3, 4, and 5.
FINGER - Appears following Mission 6.
EYE - Appears following Mission 6.
GRAY WALLABY - Appears following Mission 6.
BLUE CHAMELEON - Appears following Mission 6.
MIDNIGHT MASTIFF - Appears following Mission 6.
WILD STALLION - Appears after two of either Missions 7, 8, or 9.
MAD WALLABY - Appears after two of either Missions 7, 8, or 9.
ASSASSIN HARRIER - Appears affter two of either Missions 7, 8, or 9.
HUNTING STALLION - Appears after two of either Missions 7, 8, or 9.
FRIGID MONGOOSE - Appears after two of either Missions 7, 8, or 9.
CRYING STURGEON - Appears after two of either Missions 7, 8, or 9.
BITTER CENTIPEDE - Appears following Mission 12.
ROARING CAPYBARA - Appears following Mission 12.
PIRATE CAPYBARA - Appears following Mission 12.
NIGHT TREE FROG - Appears following Mission 12.
Silent Hills in Africa:
If you played PT, the demo that was released to promote Kojima's now-canceled Silent Hills project with Guillermo del Toro, you likely heard a recording that outlines a horrific murder. In Metal Gear Solid V: The Phantom Pain, you can find and listen to that same recording. Look for a radio positioned on the floor near one corner of a tent, just beyond an outpost encampment in Africa (it's near the site of Mission 20: Voices).
Rescue Hideo Kojima:
You can rescue Hideo Kojima, the creator of Metal Gear (and this game's director), in the Side Op 112 Intel Agent Extraction mission. Once you have done so, he'll head back to the Mother Base.
Fulton extract the puppy at the start of Mission 4 (he is at the landing zone where you leave the helicopter). If you missed this, you can replay the mission. Alternately, he can be found at the landing zones of Mission 3 and 5. Return to Mother Base (either complete the mission or call back the helicopter to abort) to view a cutscene with the dog when you arrive at base. Then, successfully complete Missions 7, 8, 9, 10, and any other two missions of your choice. Next, return to Mother Base, and the puppy will be grown up; you will see a cutscene when you arrive. D-Dog will now be available as a
buddy, and you will get the "Cry Havoc" achievement.
Note: If he is not grown up yet, play a few more missions, and return later.
At the end of Mission 11, do not kill Quiet (in the cutscene where you hold the gun to her head). If you have killed her, you can replay the mission. Successfully complete Mission 14 to unlock Side Op 111: Visit Quiet. Visit her on the medical platform of Mother Base. When you arrive at the helipad, go down the stairs in front of you to find her cell. Then, call back the helicopter to leave the area to view a cutscene with Quiet. She will now be available as a buddy, and you will get the "Speechless" achievement.
A Four-Legged Friend:
You can find a puppy that will grow up to be an awesome dog, useful for tricky stealth situations later in the game. To find the pup, travel north of the Spugmay Keep in Free Roam mode, several missions into the game (Episode 04: C2W works well). Wander around in the vicinity of the landing site for a bit during the daylight hours and listen for dog barks. The puppy should run up to you eventually, and then you can head back to Mother Base to find him waiting. Befriend him and check in every few missions. Eventually, he'll be able to join you out in the field and alert you to the presence of nearby enemies.