Here is the full list of all 12 Castlevania: Symphony of the Night achievements worth 200 gamerscore.
Defeat 10 consecutive enemies using special weapons without getting hit.
Explore 200.6% of the game.
Collect a bank of $100,000.
Unlock the Inverted Castle.
Defeat 10 consecutive enemies using only magic without getting hit.
Collect all five familiars in the game.
Obtain the Bat, Wolf and Mist transformations.
Defeat Gaibon and Slogra.
Defeat 10 consecutive enemies using standard weapons without getting hit.
Defeat Dracula in the Bloodlines stage without getting hit.
Unlock/Cast all eight of Alucard’s spells.
Finish the game, including the inverted castle, as Richter.