Hmmm... I can run as Tails, my favorite Sonic character, and provide an explanation for the reformation.<br/><br/>Tails is worried that one of his friends is going to get killed in the endless battles with Robotnik. Being a smart little fox, he builds a reformation chamber using de-robotisciser technology and chaos emerald power. You are attuned to the machine by having a full body scan done, which takes a DNA pattern and molecular level mapping, and a pin sized implant that allows it to recieve and back up your memories in real time. The tricky bit, which needed an infusion of chaos emerald power is to allow it to link to your astral form.<br/><br/>If you die, a robot blank is slotted into the machine, and modified to match your physical form, then de-robotiscised into flesh and blood. Your memories are imprinted as the brain is created, and your astral form is diverted from wherever it was going to the re-created body. Result, you're back.