You, being a member, and being the second strongest non-human member of G.U.N, were tasked to go with Knuckles to the past to collect the Chaos Emeralds, believing it was the only chance to stop "Sonic"

The person in the control center uses the microphone, giving off the signal. "Both of you, ready to go."

The Past sign started to spin aggressively, ready to send you and Knuckles to the past, and with a flash of light, you and Knuckles appear in Green Hill, before "Sonic" killed and ate Eggman. Knuckles looked at you, his face focused. "Don't get distracted, let's find the Emeralds to stop this.. 'Thing' from gaining so much power, and maybe even save Tails in the process."