Sonic and his friends go on a galactic quest to take down the Metarex once and for all. (including Chris, who manages to bring himself to Sonic's world, even to the point of regressing to his younger age). Using Tails' massive space ship known as the Blue Typhoon and the power of Knuckles' Master Emerald, they travel through the galaxy, putting everything right to all the wrongs set by the Metarex. But as the battle against the Metarex rages on, the price of victory becomes even more costly then they could ever imagine....