Unlock Nobel Gundam:
On stage 38 don't destroy the Nobel Gundam and convince Allenby with Rain on stage 41. Then destroy the Nobel Gundam.

Unlock Tekkaman Rapier:
Have Tekkaman Blade defeat Tekkaman Evil on stage 34 and Tekkaman Axe on stage 36.

Unlock Gai Daigouji:
On stage 21 take the Nadesico Route and he will join during stage 44 on the Nadesico Route.

Unlock Fourth Original Mecha:
Complete the game with the Bellezelute, Coustwell and Granteed.

Unlock IWSP Pack:
Go with the Archangel on stage 11 and 37.

Unlock X Aestivalis:
On stage 32 take the Nadesico Route.


Unlock Everything
When you have completed 5 playthroughs using the same original Saveslot ALL unlockables will be unlocked on the next playthrough regardless if the requirements were met.