The Seedrian Trilogy is a 3 part game dedicated to seedrians. It features 3 games (Seedrians Unite, Adventure to the future, Battle for Survival). The main plot is for Seedrians to find a new home where they can thrive and continue their spieces.
The 1st game of the trilogy, where the team gathers up and begins the search for a new home. This is also the only game that features a character that isnt a seedrian (Xylon the Electric hedgehog)
There are 2 teams, the main team (playable characters) and the "background team" (Supporting characters that can only be playable in Free Play)
The Seedrian Trilogy: Seedrians Unite can be played on the Wii, DS (All types) and Xbox 360 (not Knect)
Free Play is an option which is shown after you have loaded a saved game, on Free Play you can redo any of the levels with a character from any team (Background and Main). If the game is completed, you unlock Heartia , Dark Cosmo (otherwise known as Possesed Cosmo) and Super Galaxina.
If you die 8 times in a row on a level, then the ghost of Heartia can be seen floating at the start of the game. If you talk to her, she offers a helping hand saying "Are you in need of Help? My spirital power can lead you to the goal" and if you select Yes (out of Yes or No), Heartia will go into you, and a computer controls the character you are using to the goal. It is also known as Super Guide.