Here is the full list of all 12 Castlevania: Harmony of Despair achievements worth 200 gamerscore.
Completed Hard Mode.
Destroy the lord of Castlevania.
Jump kicked 30 times in a row without touching the ground.
Brought a comrade back from the dead.
Defeated a boss with 5 players in skeleton form.
Defeated a boss using sliding.
Defeated an enemy by hitting back a Skeleton's bone.
Defeat a boss using a Dual Crush.
Defeat an ally who has been seduced by the enemy.
Collect 300 different types of items.
Amass 1,000,000 gold.
Rack up 10,000 enemy kills.