Here is the full list of all 12 Half-Minute Hero: Super Mega Neo Climax achievements worth 200 gamerscore.
Received every title.
Got all available equipment in single player mode.
Cleared Hero 3.
Cleared Hero 300 in Hard Mode.
Cleared Hero 300.
Reached every ending in Hero 30.
Cleared Hero 30.
Cleared "Cursed Hero" without defeating Sasha.
Allied with all available NPCs.
Became 30 times the True Hero in multiplayer mode.
Offered a total of 3000G to the Goddess in a quest in single player mode.
Prayed to the Goddess for the first time in single player mode.