Metal Gear Solid: Portable Ops/Unlockables

There are many features that can be unlocked in the game.

Stealth Camo
In order to unlock the Stealth Camo, you need to attain a Tech level of 99.

Extreme Difficulty
In order to unlock the Extreme Difficulty, you need to beat the game once.

Boss Rush (EU only)
In order to unlock the Boss Rush mode, you need to beat the game once.

Cunningham
Beat Cunningham on any difficulty by Stamina kill and beat the game before January 1st 1971.

Cheat Code:
 * (NA)
 * (EU)

Gako Soldier
Cheat Code:
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 * (EU)

Gene
(NA) Recruit a cumulative number of 200 soldiers and beat Gene by Stamina kill on one playthrough. (EU) Complete Boss Rush mode.

Cheat Code:
 * (NA)
 * (EU)

NULL
Deplete either of his Health/Stamina bars in each fight, and complete the game.

Cheat Code:
 * (NA)
 * (EU)

Ocelot
Recruit Sokolov, then head to the Silo Entrance and interrogate the Soviet Officer located on top of the bridge area. Wait until you receive a Spy Report from the Town. Head to the Town at nightfall and locate the Government Official in one of the upper buildings, then interrogate him. Head to the Airport and interrogate the FOX soldier at the control deck in order to learn a radio frequency: 141.23. Recruit EVA. Head to the Ravine and infiltrate its communication building. To do so, find the Key located on the second level of a nearby cave. Enter the building and contact the frequency (141.23). After the call, complete the game.

Cheat Code:
 * (NA)
 * (EU)

Teliko
Have a Metal Gear Ac!d save on your memory stick, and start a new game on an already completed save.

Cheat Code:
 * (NA)
 * (EU)

Venus
Have a Metal Gear Ac!d 2 save on your memory stick, and start a new game on an already completed save.

Cheat Code:
 * (NA)
 * (EU)

Zero
Have a Metal Gear Solid: Digital Novel save on your memory stick, and start a new game on an already completed save.

Cheat Code:
 * (NA)
 * (EU)