Because who needs a manual when you can have the official blueprint revisions?
When Dr. Eggman first created the Chaos Emeralds-empowered Sonic, he had a few... interesting design choices.
After a few too many near-death experiences, Sonic decided to ditch the Chaos Emeralds for a more... shall we say, 'practical' design.
When Sonic's ego couldn't handle the fact that he was, you know, actually dead for a few minutes, he decided to add a few... let's call them 'safety features'.
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