70's
Robot Anime Geppy-X
64/74 Shiki Mode
At the title screen, press UP, Up, Down, Down, Right, Left, Right, Triangle.
Atlancer Mode
At the title screen, press Left, Right, Right, Down, Left, Left, Right,
Triangle.
Movie Version
At the title screen press Down, Down, Left, Down, Down, Left, Down, Triangle.
Queen Fairy Mode
At the title screen, press Left, Right, Left, Down, Down, Right, Right,
Triangle.
Star Geppy X
At the title screen, press Down, Left, Left, Down, down, Right, Right, Triangle.
Wild John Mode
At the title screen, press Up, Down, Right, Up, Down, Right, Up, Triangle.