Sonic the Hedgehog 3 Strategy Guide (Brady Games, Unknown Date)

The Sonic the Hedgehog CD Strategy Guide by Brady Games gives a complete walk-through of Sonic the Hedgehog CD. Page 82 contains an interesting bit, as it refers to a final battle with Metal Sonic, even though normally he is never fought, but instead it is a head to head race which ends when Metal Sonic crashes into a wall. It could be that the final room before Robotnik had this Metal Sonic battle instead of 2 firefly enemies.

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