Unlock Asuka

Beat Story Mode with any default Takara character (Licca, Takao/Tyson Granger, Optimus Prime, Microman).

Unlock Bimbougami

Clear Story Mode with all Hudson characters (Bomberman, Momotarou, Master Higgins/Takahashi, Yugo, Manjimaru).

Unlock Manjimaru

Beat Story Mode with any Hudson character (Bomberman, Momotarou, Master Higgins/Takahashi, Yugo).

Unlock Megatron

Clear Story Mode with all Takara characters (Licca, Takao/Tyson Granger, Optimus Prime, Microman, Asuka).

Unlock Moai

Cleat Story Mode with all Konami characters (Power Pro-Kun, Simon Belmont, Twinbee, Solid Snake).

Unlock New Stages

Unlock the Artificial Sun stage by clearing Story Mode with Moai (from Gradius)
Unlock the Oil Rig stage by clearing Story Mode with Solid Snake (from Metal Gear)
Unlock the Tree House stage by clearing Story Mode with Megatron
Unlock the Devil Orchid stage (Manjimaru) by clearing Story Mode with Manjimaru
Unlock the Floating Continent stage by clearing Story Mode with Bimbougami

Unlock Solid Snake

Beat Story Mode with any default Konami character (Power Pro-Kun, Simon Belmont, Twinbee).