Super Robot Taisen: Original Generation Cheats...
Gespenst Mk-II S
Destroy the R-GUN on stage 30 on Ryusei's path.
Gespenst-R
On the Kyosuke Route, make sure Guilliam is at least level 23 by stage 19.
Graviton Launcher
Make sure your opposite main character (Ryusei or Kyosuke) has at least at least 55 kills by stage 32.
Grungust
Destroy the R-GUN on stage 30 on Kyosuke's path without getting the Huckebein 008L.
Guarlion
Destroy it with either Task or Rai on stage 24.
Hero Symbol
Daitetsu (Ryusei Route) or Lefina (Kyosuke Route) must be at least level 35 by stage 35.
Huckebein 008L
Have Ingram be at level 32 before stage 30 (Ryusei Route) or Villeta at level 23 by stage 19 on the Kyosuke route.
Kai
Take the Kyosuke Route.
Keep the ability to combine into SRX
Take the Ryusei Route.
Lion-F
Take the Ryusei Path.
New Game+
Beat the game once with Kyosuke and Ryusei to unlock New Game+
R-GUN
Destroy it on stage 30.
Shishio Blade
Make sure your main character has at least 50 kills by stage 26. Destroy Zengar on stage 26. Be on Hard Difficulty.
Soul of Metal
Daitetsu (Kyosuke Route) or Lefina (Ryusei Route) must be at least level 38 by level 38.
Valcion Kai
On stage 28, reduce the HP of the Valcion Kai below 10% without destroying it.
