Flying Dragon

Play with Ryumaou:
Finish the Ryumaou tournament.

Unlock Bokuchin as playable character:
Beat Bokuchin

Very hard level:
Highlight the "Hard" option, then press Right several times
until "Very Hard" option is displayed.

Very easy level:
Highlight the "Easy" option, then press Left several times
until "Very Easy" option is displayed.

Unlock platinum fighters:
Choose the "SD Hiryu" mode and play in the circuit.
Collect 10 medals by beating the platinum fighter ten times.

Unlock Rayomau tournament:
Get 9 medals

Dark Dragon Claw
Finish the Ryumaou Tournament as Yuka and reach S rating with 1 minutes,
2 round in normal mode.

Learning great combos in free training:
Go to the practice mode on Virtual Hiryu. Hold Guard + C-Right.