The costume name comes from that Sonic's fur turns gold when transformed into Super Sonic.
StrikeForce Kitty 2
"Gold Hedgehog" adds 11 strength, 5 health, and 13 speed to that kitten, for a total of 24 strength, 31 health, and 29 speed, from "Hedgehog".
Note: The top/head part of "Gold Hedgehog" is slightly offset from "Hedgehog". It is unknown if this is an error.
StrikeForce Kitty: Last Stand
"Gold Hedgehog" is a cosplay that can be obtained from defeated raccoons in StrikeForce Kitty: Last Stand, look on pages in the "Melee" category.