*During your birthday party a mysterious entity consumed your friends and whisked you off to a white void. You then come across an area gate that looks familiar, you decide to enter it. It was Green Hill. Then after beating Green Hill, your best friend Miles 'Tails' Prower turns from a statue frozen in time, to alive and well. You then come across another area that reminds you of the Chemical Plant, and it was. After beating the Chemical Plant, you save Amy Rose. You then move on to a place that you can safely assume is Sky Sanctuary, and is. You then beat Sky Sanctuary and save Knuckles before going to a mysterious gate that reminds you of the beast that abducted you and your friends. You decide to enter the gate. It transports you to a mysterious hallway with a wall of mirrors, as you look inside the mirror it looks like your reflection... But something is off. A voice then booms from the end of the hallway where a giant door lies. It's Dr. Eggman.

Eggman: Take a good look at yourself Sonic! 'Cause It's the last look you'll get, before I close your eyes forever! He then laughs maniacally

Before you can react, the other Sonic is running towards the closing door. You try to catch up but there's no use. You stand outside the gate's first opening. While you wait, you realise there are 2 Tails as well. The other Sonic exits the gate and he's a younger version of you. After the 2 Tails explain what's happening, you realise that the fog has cleared up and you can now advance towards Speed Highway

Good luck