If You complete the indicated task You'll get the allotted gamerscore.
Complete The Game (25) - Finish the game by defeating Mother Brain.
Where Credit Is Due (25) - Watch the entire in-game credits roll.
Dark Force (25) - Defeat Dark Force.
Level 30 (25) - Advance one of your party to Level 30.
Level 20 (15) - Advance one of your party to Level 20.
Level 10 (15) - Advance one of your party to Level 10.
Oh Dam (15) - Open all four dams.
Oh Yeah! (15) - Acquire the Laser Cannon.
Big Spender (10) - Spend 1,200 Meseta on one item.
Escapipe (10) - Use an Escapipe to escape a dungeon.
Hidapipe (10) - Use a Hidapipe.
Nido? (10) - Reach the Tower of Nido.