Bandana and Stealth camouflage:
Complete Extra Ops 119 with an "S" rank for the Bandana or complete Extra Ops 050 with an "S" rank to unlock Stealth camouflage.
True Last Battle (Zeke Battle) and Ending:
There are many requirements for unlocking the true last battle that don't have to be done in any particular order. First, make sure you complete all 6 Main Ops "Zadornov Search" missions, which are unlocked after the last mission (Peace Walker Battle 3). The Mother Base must also have been upgraded to 2 plants, which is achieved by first having a Level 40 Intel Team (just move a bunch of recruits to that section to increase its level) and then completing 13 Extra Ops missions (except Target Practice, No Limit or Training missions) to upgrade the base. It doesn't matter if the Extra Ops missions were already completed, you can repeat the same mission 13 times if you wish. You'll receive a message that the Mother Base has expanded. Do this twice. Once done, you must have collected all the Metal Gear ZEKE basic parts (collected by beating bosses) and must have the Railgun installed (which is gotten from S-Ranking the Chrysalis Battle). Also, you cannot have Metal Gear ZEKE assigned to an Outer Ops Team. After meeting all of those requirements, you'll trigger a call from Kaz informing you that Zadornov has escaped his cell yet again. So go to Extra Ops Target Practice #1, you'll see Zadornov on the 2nd floor. After the cutscene, the true last battle will be unlocked. If by any chance you don't get the call about Zadornov escaping that 7th time, then just keep completing Extra Ops missions until your Mother Base grows more and you'll eventually get the call.
A Country Without An Army - Cleared Chapter 1: A Country Without An Army.
A Nation Reborn - Cleared Chapter 3: A Nation Reborn.
An Army Without Borders - Cleared Prologue: An Army Without Borders.
Basilisk Eater - Defeated Pupa, Chrysalis, Cocoon, Peace Walker.
Costume Collector - Obtained every costume.
CQC Six Shot - Performed CQC six times in a row.
Delivery - Sent an item using Delivery.
Divine Wind - Collected a soldier using a divine wind.
Don't you have anything else to do with your time? - Rolled 100 times or more in a single mission.
EXTRA OPS All Cleared - Cleared all EXTRA OPS missions.
EXTRA OPS All Rank A - Cleared all EXTRA OPS missions at Rank A or higher.
Fulton Recovery Veteran - Reached 300 Fulton recoveries.
Hideo Kojima - Recruited Hideo Kojima.
Hold-Up Artist - Reached 100 hold-ups.
Huey's Thoughts - Read Huey's love letter.
I feel... safe - Wearing a cardboard box gives you that feeling of inner peace.
I'm dead serious - Threw a chaff grenade at ZEKE (single player only).
Indirect Attack - Attacked enemy soldiers by blowing up an oil drum or truck (single player only).
Kaz Mania - Obtained Rank S on a date with Kaz.
Kuwabara, Kuwabara - Heard a ghost on the radio.
Launched ZEKE - Complete Metal Gear ZEKE.
Leap of Faith - Performed a Leap of Faith.
Lethal Enforcer - Reached 100 kills.
MAIN OPS All Rank A - Cleared all MAIN OPS at Rank A or higher.
Mech Catcher - Captured a mech.
Monster Hunter - Cleared all hunting quests.
Outer Heaven - Cleared Chapter 5: Outer Heaven.
OUTER OPS Sortie - Carried out a mission in OUTER OPS.
Paz Mania - Obtained Rank S on a date with Paz.
Paz's Thoughts - Read all of Paz's diary.
Strangelove's Thoughts - Read all of Strangelove's memoirs.
Stun Specialist - Reached at least 100 stun attacks or sleep-inducing attacks.
That looks tasty! - Nicely cooked a ration.
The Illusion of Peace - Cleared Chapter 4: The Illusion of Peace.
The Phantom Hero - Cleared Chapter 2: The Phantom Hero.
Trader - Carried out a trade.
VERSUS OPS All Rules - Played using all of the rules in VERSUS OPS.
You have far too many Game Overs - Reached 50 or more game overs.
You're pretty good - Shot enemy right in the middle of the rear end.
Completed ZEKE - Customized ZEKE's head parts and foot parts with special AI weapon parts.
Elite Forces - Cleared 'Capture the Enemy Base 06' in OUTER OPS using only soldiers.
EXTRA OPS All Rank S - Cleared all EXTRA OPS missions at Rank S.
Gives me infinite ammo - Acquired Infinity Bandana. Never worry about running out of bullets ever again.
MAIN OPS All Rank S - Cleared all MAIN OPS at Rank S.
Special Staff Recruiter - Assembled all special staff members.
Stealth camouflage - Acquired stealth camouflage. Never worry about being detected ever again.
Steel Eater - Defeated all AI weapons.
Big Boss - Cleared all MAIN OPS and EXTRA OPS missions at Rank S.
Vic Vos - Reached a total of 20,000 or more Camaraderie.
Vic Boss - Earn all Bronze, Silver, and Gold trophies.