Not to be confused with the Bad ending in the older version of Nightmare Beginning.
Sonic walks through his mind past demonized Tails, who says "Please don't leave me Sonic!", demonized Knuckles, who says "Stay here buddy - from here there is no escape.", and demonized Eggman, who says "Seems that you are met with something new. This new - failure..."
Sonic reaches (Classic) Exetior, who says "It's over". After touching him, Sonic appears in Suicide Hill, where he walks by and sees the corpses of his dead friends and Eggman along the way. He finds spikes, but as he is about to jump into them and kill himself, the ghosts of Tails and Knuckles tell him to not do it, saying that he can't save them but he has to protect the rest, and to keep hope and determination. They fade away, and Sonic is shown crying. He soon closes his eyes.
It then shows demonized Tails piloting the Tornado with Exetior and Knuckles on it, and Exetior says "Get ready girls! We are going!"