|This transformation exists primarily or exclusively within the Pre-Super Genesis Wave continuity.
Information in this article may not be canonical to the storyline of the games or any other Sonic continuity.
Eco Sonic is an alternate form of Ultra Sonic. He has only appeared in Sonic the Hedgehog #71.
He achieved this form while running at high speeds through the Great Rainforest while using Nate Morgan's Super Emerald to return to Knothole in regular time. He has only achieved this transformation once (in #71), and it seems probable that the environment influenced his change to this state as well as Solar Sonic and Polar Sonic.
Powers and abilities
As Eco Sonic, Sonic's already-amazing speed is enhanced to a new level, being capable of moving even faster than Polar Sonic.