No voices, but I figured it all out.
Shadow meets Sonic on the outskirts of a city. "You're too late, Sonic. Tails is clearing the civilians out of the city as we speak." Shadow says. "Too late? Sonic the Hedgehog is never late. I'll dance in a pool of humie blood by the end of the day!" Sonic insists before taking off toward the city. Shadow gives chase, pleading with the bloodthirsty hedgehog to show mercy, but Sonic continues trying to outrun Shadow, leaving a path of destruction in his wake. He's frustrated to find no civilians, despite unnecessarily breaking every window searching for them. He suddenly comes up with the brilliant idea to lure Shadow in by faking his own suicide. Sure enough, sympathetic Shadow comes to try to talk him down but Sonic conceals himself in the water when he sees Tails coming so he can get a double kill. "Shadow, I got everybody safely out of the city. They're building space colonies on Mars. Since no one can stop the blue demon, our only choice is to leave the planet and hope he can never follow. Here, I brought you the chaos emeralds so you can survive the cold vacuum of space," says Tails as he prepares to throw them to Shadow.
"Donkey masturbation!" Sonic shouts at the last moment. Such an unusual and foreign mental image is too much for the young fox's mind to handle and he bungles the throw in a moment of terrified brain porn. "Oops! Sorry Shadow," Tails says sincerely, "I'm low on fuel. I'm heading back into town to refill it and then I'll come back for you." With that he flies off. Underwater, Sonic becomes Urine Sonic. Luckily, Shadow becomes Super Shadow from the one emerald that Tails was able to pitch his way. The two fight for a while. At one point Shadow assumes that Sonic is just hurting inside because no one loves him. Shadow offers his body to Sonic, adding a suggestive wink, but Sonic's senseless thirst for violence causes the offer to have no effect. Robotnik, the genius responsible for colonizing Mars and saving the human race, shows up and takes a chaos emerald as an environment-friendly power source. Soon after beating up earth's defender, Shadow, the evil blue hedgehog turns his eyes on Tails who has returned to try to save his friend. "Shadow should be right about... GAH! Sonic?!? Oh no!" Tails exclaims as he tries to bring the plane to a halt so he can escape. "Take it up, fox. NOW!" Coerced by threats from Sonic, Tails flies the two of them into space. "Show me where the one responsible for this plan to move the humies to a safe location is." Sonic demands. "I... But he's saved so many lives from your unexplainable need to destroy everything just for fun." Tails says as he struggles with thoughts of doing the right thing against thoughts of his own safety. "Foxes can't breath in space in open cockpits. You're only alive because you're inhaling the life-giving pure evil that rolls out of every orifice on my body. You WILL obey... Or die."
Finally, Tails takes Sonic to meet with Robotnik. Tails triggers the silent "kill me" signal on his plane, selflessly warning Robotnik that the terrorist hedgehog is onboard. Sonic dodges the attack, though and begins smashing everything with reckless abandon, simply because it's there. They nearly stop him but Knuckles shows up with a cloak. Why would Knuckles need to hide his identity? Simple, because he has adopted Sonic's "break everything that can be broken" philosophy and knows that he would be arrested on sight. Together they break things. Sonic stays up top to break things but Knuckles goes inside the ship. Sonic nearly dies, but the tears of Amy resurrect him. Knowing that he's brought so much pain to a young girl turns him into Sadistic Sonic, his ultimate form. Knuckles is still inexplicably wearing his "disguise". After countering the ship's security, he attempts to break the master emerald but fails. In the aftermath, he sees that Robotnik has something not broken and breaks it too simply because he can. Finally, Sonic once again takes Tails hostage, demanding that the fox take him to the humans' new world. I can't wait for the sequel.