Derpy was about to step out of the TARDIS when it suddenly started moving again. It was going back to present time. The doors opened and Derpy stepped out. She was inside of Dr. Whooves house. Everything looked normal. She heard muffed noises coming from a closet. It had a window in it and Derpy peaked in. It was Dr. Whooves and Colgate. Derpy wasn't sure whether to trust them or not though. Still, though, even if they were changelings, what could two extra Chrysalises do that four Chrysalises couldn't?
Derpy opened the door and took off some tape that was covering their mouths. "Oh thank heavens you're here. I really need your help!" Dr. Whooves said. Derpy was up against the wall, frightened. She didn't speak. "You did get that letter, right? I knew Queen Chrysalis was plotting something so I placed the letter in my mailbox, hoping you would find it." he continued. Derpy was still unsure but decided to talk "How do I know it's really you?" she asked. "Look outside. Have a see for yourself." Colgate replied for Dr. Whooves.
Derpy leaned outside the window. The skies were red and the clouds gray. All the ponies had chains on them and were being forced to work as slaves for the changeling army. They had completely overtaken Ponyville and possibly all of Equestria, although it was impossible to tell now. "You see all of the destruction right? Even as you were speaking to the fake me and the fake Colgate earlier, I was trapped in this closet. I, however, was not affected by the time alteration because my house has a time bubble as one might say. Time flows forever in here and nothing can change that, unless the bubble, of course, were destroyed. Chrysalis, however, did not know this and just left me tied up in here instead."
Derpy was no longer frightened. The way everything looked outside and Dr. Whooves' explanation was enough. Now she wasn't speaking but not from fright, but from shock. All of this was happening so quickly. "Oh, and the TARDIS has it's own time bubble as well. That's why you weren't affected." Dr. Whooves continued. Finally, Derpy was able to snap out of her shocked state and fully untied both Dr. Whooves and Colgate.
"I know exactly how to fix this. We can use my time bubble as a time explosion. However, if we are to do so, we must go to a point before any time jumps or time landings were made. While Chrysalis was talking to you, I heard that she was planning on going back in time to the wedding. This means we must use the TARDIS to go to a point in time before the part of the wedding you arrived at. Only you know where you arrived so only you know where you must go." Dr. Whooves said.
"Once there, you have to detonate the TARDIS yourself. I, unfortunately can not go with you. This is my TARDIS and my time bubble so if I change time with you, the very fact that I am telling you this right now might be erased from existence and space-time will cease to exist. You, on the other hand, have nothing to do with any of these time jumps so you are the perfect candidate. You will have to go back alone, with the TARDIS and detonate it. Afterward, the TARDIS will go automatically go back to the present. Because you are from the timeline without Chrysalis' reign, nothing will happen to you as you are only restoring your own timeline. However, I can not guarantee that you will be in the present in time." Dr. Whooves continued.
"In other words, if you blow the time bubble up, and you're not in the present yet, you will be changed into the Chrysalis timeline for a split second. Once you're changed back with the result of the time bubble, you wont remember any of this. Hopefully, that wont happen and you'll be able to remember all the events of which occurred today. Or, not today, but you know what I mean. The last thing I must say is that whether you be in the present time for you to remember or not, I will not remember no matter what." Dr. Whooves continued to explain.
"The TARDIS' time bubble and the time bubble of my house are connected so when you detonate the TARDIS' time bubble, so will this one. When my time bubble explodes, I will no longer be protected from time anomalies. I may not be able to remember the brief friendship between you and me but I will be able to remember the events that have occurred here. Everything I just said 'I know how to fix this' to what I am saying right now is being recorded behind me. I need you to take it with you so that it does not get affected by time. If it does, that means you didn't get to the present in time and even you won't remember anything. However, if you are still protected in time, this recording should stay in tact. When you return to the present, I want you to come straight back here. I'll have no memory of you but all you'll have to do is give me this recording and I'll believe every word you say. We haven't got much more time." Dr. Whooves grabbed the recording and placed it in Derpy's hooves. Suddenly, the doors to Dr. Whooves' house burst open.
"Go. Now." Dr. Whooves said as he shoved Derpy into the TARDIS. Dr. Whooves was going to close the door on her when the changelings grabbed him. The changelings' horns glowed and then so did Dr. Whooves and Colgate. They screamed at the bottom of their lungs. The changelings began talking "We have direct orders from the queens to eliminate you. You are a threat to the mission and can not be tolerated." Dr. Whooves and Colgate were in dear pain but Dr. Whooves somehow managed to speak "Ahh! Go! Close the TARDIS and go off! Remember! Ahh! If you succeed, none of this will happen! We'll be fine! AHH!" He couldn't talk anymore. It was a terrible sight seeing her friends in pain but Derpy knew what she had to do. She closed the TARDIS and continued to hear screaming. Then, all of a sudden. There was a splat on the TARDIS. There was a semi-transparent window on it but it was no longer transparent. It was red. And, there was complete silence now. Derpy knew exactly what had happened and began crying. The changelings were now banging on the TARDIS trying to get it opened. This scared Derpy into realization and she set it to go back in time once more. This might have been her final time jump.