Here is the full list of all 10 Steredenn (JP) trophies - there are 8 bronze and 2 gold.
Destroy a Bomber boss
Destroy a Frigate boss
Destroy a Destroyer boss
Destroy a Cruiser boss
Destroy a Carrier boss
Destroy a Battleship boss
Destroy the Mothership
Destroy the Nemesis
Finish the game once
Beat the game using the Blaster only