Sigma Star Saga Secrets and Unlockables (GameBoy Advance)

Sigma Star Saga is a hybrid role-playing game (RPG)-space-shooter for the Game Boy Advance. The player explores a standard 2-D overworld but is transported into space for side-scrolling shooter random battles. In this game, Ian Recker goes undercover against Earth's enemies, the Krill, in a battle to save the planet.

There are two distinct portions of the game: an overworld where you control Recker directly and side-scrolling shooter random battles. In the overworld, Recker travels around either talking to people to advance the plot or searching for items and data on one of several planets. As the game progresses, your abilities expand: you are given more weapons to fight the local flora and fauna and you receive power-ups that let you pass different barriers to your progress.

Unlockables

New Game +
To unlock New Game +, beat the game and wait through the credits. At the end, the game will prompt you to save. Do so and the next time you start the game the completed save file will have a gun data icon by it. New Game + allows you to replay the game with all of your old gun data and gives you access to several new endings.

Psyme endings
In the final battle with psyme she is in a battle worm and you have to fight her. If you only shoot out the three cannons on top she remains alive to the end. But if you shoot out the eyes on the bottom of the screen she dies and is out of the last cut scene.

Scarlets Endings
Whether Scarlet appears in the ending or not depends on your picking up the Virus while on earth the second time. You can find it in the room above the one where Zart and Tierney were working. You cannot return here after you have left, so decide what ending you want here. (Only available in New Game +)

Unlock Sigma Ship
Defeat the game once to unlock the Sigma Ship in random encounters.

Secrets

Final Boss trick
The final battle with the overlord can be very difficult. However, there is one trick to beat him. Equip a gun type that can shot at a down-left angle. Then simply fly right in front of his forehead, the only place none of his attacks can reach.

No Random Battles
Once you obtain the Girl Wings, you can use them to avoid random battles. You cannot enter a random battle while hovering. So if you repeatedly use the Girl Wings as a means of travel instead of walking normally, you'll never be summoned to play a random level.

Check out the video below for some great gameplay footage: