Future Tactics: The Uprising
  
PS2
  

Big Heads: 


During play, press Up, Left, Down, Left, Down, Up, Up, Left 
Disco mode: 


During play, press L1, Left, L1, Left, R1, Right, R1, Right
Low Gravity: 


  During play, press Up, Up, Up, Up, Up, Up, Down, Right, Up
Level select:


  Beat the game twice.

Team power option:


Get two head shots in a row, then check the Battle Mode screen.
Custom
    option:


Get  100% hit head shot status twice in a row,   then check the Battle Mode
  screen.

Humans and creatures option:


Fully
upgrade one character's weapon, then check the Battle Mode
  'team types' screen.

Defeat leader option:


Beat an episode with all team members' health at 100%, then check the Battle
Mode 'objectives' screen.




Thanks to Revolution readers jumanji and Bulls!