Derpy drops a piano on you. 
"Sorry." she says.
"Ah man, you awoke up my daughter"
Luna struggles with conflicting feelings of confusion and Righteous Anger.
*twitch*You begin to twitch at just how much this sucks. You were hoping that Nightshade would stay asleep though all this chaos. You really didn't want to have to explain to Cadance that you have a filly who lives in your bag and thinks she's your daughter. Well... at least not at first. Maybe in the middle of explaining what's been happening to you, then you would explain the whole 'daughter' thing. You just sigh and look over to Luna and say
"Ah man, you awoke up my daughter."
You don't know why you said that, but it just felt like that response was called for. Luna expression appears to be struggling with conflicting feelings of confusion and righteous anger. Cadance looks like she might faint and the husband looks surprised as well. As for Celestia... her face is still blank. You seriously start to think you broke her! Nightshade giggles besides you and says
"*giggle* They're making really funny faces daddy!"
She then starts to make faces too, one being a... duck face? You chuckle at her silliness and decide to take advantage of Luna and the husband's confusion and shock to escape. You look down to Nightshade and are about to tell her to jump on your back when...
Derpy drops a piano on you.
*smash* A piano falls right on top of you! Luckily, the piano didn't fall on your whole body. Unluckily for you it landed on the lower half of your body, pinning you down from your shoulders down. Your vision is a little hazy, but you hear Nightshade and Cadance call out "Daddy!" "Bugze!". Your vision finally turns back to normal and you see your grey pegasus friend from Ponyville looking at you worried.
"Sorry, I just don't know what went wrong. Are you okay new friend?" She asks you in a worried tone.
You would have wondered how she knew it was you, but you are in too much pain to really care at the moment.
"I'm fine (my spleen...)." you tell her so that she doesn't worry anymore. "Oh, I never told you my name and I never got yours."
"My name's Derpy."
"I'm Bugze (think I re-broke some ribs...)."
Before you can ask her for help, her eyes suddenly go up in shock and she says "Don't worry Bugze, I know just the stallion that can help you!" And with that the gray pegasus flies out of sight. Before you could wonder what she means by that, you hear Nightshade yell "Let me go!" and you quickly try to angle your head to where you heard her scream come from and you see...
The royal alicorns (and Shining) get into an discussion/argument on what to do with the potential reincarnation of Nightmare Moon in front of you and her (Luna being the most hostile (Luna would most likely NOT be on good terms with a mini-version of her evil half) and Cadance being the most on-your-side-y; vouching for Bugze and commenting on how cute Nightshade is). During their argument, one of them says/does something which scares Nightshade.
A huge debate going on. You can't exactly hear them, but from the looks of it the princesses, Cadance, and her husband are arguing about Nightshade. The pony holding Nightshade in a magical levitation grasp appears to be princess Celestia. Luna keeps on pointing at Nightshade with a look of pure hatred. Cadance on the other hoof shakes her head 'no' and says something that causes the still struggling Nightshade to blush. Her husband then says something that causes Luna to shake her head 'yes'. Cadance expression changes to pure disgust and she looks between her husband and Luna in pure horror. Celestia just looks over to you in... sympathy? Of all the ponies here, why is she looking at the one enchanted coat wearing changeling with sympathy? You think to yourself confused. Then Luna says something in the RCV that makes your blood run cold...
"I SUGGEST THE GALLOWS!"
Your daddy instinct kicks in and you quickly and protectively get in front of the frightened filly in response and proclaim: "Hey! She's sorta-kinda MY daughter, and if you even think about harming a single hair on her confused adorable little mane you'll have to go. Through! ME!!!" (the last part is yelled in the RCV with such force that it actually knocks down all the nearby Royal Guards and even forces Celestia, Luna, Shining (and possibly Cadance) back a step or few).
*snap*Something deep inside you snaps when you hear that. You don't care what the others expressions are. You don't care if this is the princess you made a vow to. You don't care that she's basically a goddess who can control the bucking moon. Upon seeing the terrified look on Nightshade's face, your daddy instinct kicks in, you teleport right into the center of the group, and shoulder-shove Celestia away from Nightshade, breaking the solar monarch's magical concentration. You catch the frightened filly, teleport the both of you away from the group, and protectively put her behind you. You don't know why, but when you looked back at the group... they all flinched. You would have wondered why if you weren't so furious at the moment, You then tell them...
"Hey! She's sorta-kinda MY daughter, and if you even THINK about harming a single hair on her confused, adorable, little mane you'll have to go. Through! ME!!!"
You roar the last part in the RCV with so much force that it actually knocks over and lightly scatters all the nearby Royal Guards and even forces Celestia, Luna, Cadance, and her husband to take a few steps backwards. They all look at you in shock, but that last for only a few minutes as Luna screams...
"What."
It is no question, but a statement.
"What?!?"
Luna jumps back, fear taking hold of her eyes.
The RCV kicks in.
"WHAAAAAAAAAAAT??????????"
"What."
It is no question, but a statement.
"What?!?"
Luna jumps back, fear taking hold of her eyes.
The RCV kicks in.
"WHAAAAAAAAAAAT????!!!!!!"
Her fear quickly turns into pure rage and she begins to charge up a beam from her horn as she yells in the RCV...
"Thy terms art acceptable!" and charges up a big attack.
"THY TERMS ART ACCEPTABLE!"
Thinking quickly, you pick up Nightshade, tell her "Nightshade! Back to bed!" and shove the filly back into The Inventory before she can protest. You hope The Inventory will survive the blast, cause you know you won't. You close your eyes as you brace yourself and think So this is how it ends huh. Well at least I'll go out in a bang. But suddenly, you hear this behind you and you look behind you in surprise to see...
But then a familiar blue phone box appears
The stinking TARDIS! The door opens and you see...Derpy? She screams at you "What are you waiting for, run Bugze!" You heed her advice and you begin to run for the TARDIS as Luna fires a massive magic death beam at you. You make into the TARDIS just before Luna's death beam could hit you. Sadly you accidentally slam headfirst into the control panel, so all you see is darkness and the last thing you hear is "WHAT!"
SOMETIME LATER
"Huh...what... Anyling get the licences plate of the chariot that hit me?" You say to yourself as you come back to the world of the living. You finally get up and look around as to where you are, and you see that...your in the forest...again. *twitch* Your anger hits it's boiling point and you can't help but scream to the heavens...
You decide to verbally express your anger.
"BUCK YOU, LADY LUCK!" you scream.
"BUCK YOU, LADY LLLLLUUUUUUUCCCCCCCKKKKKKK!!!!!!"
What do you do?