During one of explorations, Shadow the crew landed on a tropical island, because the blue hedgehog wouldn't stop whinning about his sea sickness and wanting to stretch his legs.

While others were doing something productive, Sonic was running around, exploring the island thats when he found a cave and rushed right in without a second thought.

Whatever he went looked like a temple on the inside, with only slight glow radiating from behind a pillar, Sonic approached the pillar and realized there was a treasure chest but suprisingly it wasn't closed shut like a normal treasure chests he read in stories would..

Though he wasn't dissapointed when he found a bunch of gold coins and little gems hidden inside. But then his eyes caught the Necklace with jewel that resembled a... Squid's eye? That's an odd fashion choice sonic thought to himself and as soon as his hand wrapped around it his mind was struck with many voices, one the most recognizeable one.. commanding him to hide the necklace, to take it, to keep it a... Secret.