Metal Gear Acid Cheat, Codes

Viper: Gives you Viper card 173
Mika: Gives you Mika Slayton Card 178
Karen: Gives you Karen Houjou card 182
Jehuty: Gives Jehuty card 184 – This card destroys all equipment in a room.
Xmeight: Gives you card 199
Kobe - Gives you card No.200, Yuka Kosaka
Umeda - Gives you card No.201, Asaki Yoshida
Yebisu - Gives you card No. 202
Roppongi - Gives you card No.203, Eri Shibuya
The following four codes are for the Japanese version only
Sabrage: Gives you card 200
Nomel: Gives you card 201
Elyts: Gives you Card 202
Maeb: Gives you Card 203

Unlockable: Multiplayer with Wi-fi
Once you complete Stage 6, the Residential Area, Teliko has joined the mission. If you go to the options during the intermission menu, Link Battle is now available. You can link two PSPs through AD-hoc, and go head to head while controlling Snake and Teliko.

Unlockable: Special Bonus Cards

Raiden Card: Complete the game twice on any difficulty.
Solid Snake Card: Complete the game once.