Last time on The Unexpected Attack.
The crew attempts to fix the Blue Typhoon to launch into space...
"Tails needs your help to fix the Sonic Power Cannon and power up the engines."
...but the Metarex know and try to stop them...
"Shrieker. Crusher. Prevent the spaceship from leaving the planet and destroy it. Also, capture the hedgehog Sonic. If anyone else tries to get in your way eliminate them."
...leading to Starlight and Tails being controled...
When Sonic turns around to see who did it, a golden silver figure kicks the hedgehog in the chest sending him sprawling, did three back flips, and landed on the ground. As soon as both of them got up, they were shocked to see that it was Cosmo's daughter!
"She chose this of her own free will."
"Because of you everything went wrong. I can't let you escape the planet with your friends! You better surrender to the Metarex before I have to do it myself!" answered the two-tailed fox.
...another group called the Metarax to appear...
"How dare you interfere. Leave before I make you leader of the Metarax."
...Sonic turns into Dark Sonic…
A dark aura surrounded the hedgehog as Cosmo's daughter ran to him. The hedgehog dug his foot into the defeated Metarex laughing hysterically.
"That's all you got? I expected more from you. After all, the Metarex leader did send you."
The hedgehog was in front of her and grabbed her hands that were holding the chain forcing her to let go.
"I don't want to hurt you, but if you interfere with my fun, I won't hesitate to do so."
…yet they still preserve and reach space.
The Blue Typhoon started rising up into space until they were out of the planet's atmosphere.
Here's the prologue. Please read The Unexpected Attack if you haven't already.