The Freedom Fighters stumble upon a train bound for a crystal mine and Sonic finds his roboticized Uncle Chuck to be onboard. Sonic uses a power ring to temporarily restore Uncle Chuck's free will and he explains that Robotnik is after a powerful crystal, which will destroy the eco-system if taken out.
Click for Goofs Header Index Plot- If Removing 'That much active crystal' will destroy the Eco-System, how come Uncle Chuck says it's okay to destroy it so Robotnik doesn't get it?