Starlight and Big Mac

Applejack and Starlight watched Big Mac do some applebucking in the Apple Family field.

Big Mac let out some loud flatulence, to which Starlight hooted and hollered.

“Nice one, Mac!”

Big Mac looked proud.

Starlight bit her lip and ripped one.

—

Applejack looked skeptical. “I sure hope y’ ain’t plannin’ on usin’ magic to enhance those farts.”

“Please. Who needs magic when you got poots like these?”

Changeling Attack

The Changelings chased Trixie into the cave.

Trixie flashed her ass, and within seconds and a loud fart noise, smelly green mist flooded from the cave, and multiple Changelings flopped dead on the ground.

Trixie exited the cave with pride, proud of her work.

Saving The Stadium
“Their only weakness is stench,” Twilight said.

A light bulb went off in Rainbow’s head. “Twilight. They serve Canterlot Chili here, correct?”

While the Cloudsdale Chili is being handed out: “This is your ammunition. And your weapon... will be your flanks.”

The ponies all looked at eachother in confusion.

“That’s right everypony! We’re gonna fart these suckers away! And don’t get cold feet; we need everypony’s help on this. Trust me, nobody’s judging you. And if somepony next to you looks embarrassed and isn’t letting loose, just assure them that we’re all in this together! We’re all! Gonna! Fart!”

Vinyl got an idea. She pulled her microphone around to her flank and let out a nasty butt belch, the bass sound of which echoed through the stadium.

Rainbow smiled back at Vinyl. “Y’see? There’s a pony who’s not afraid to let her flatulence fly. Remember: every pony farts! And right now... everypony needs to.” She then stuck her megaphone to her ass and let one rip for the whole stadium to hear.

One by one, more ponies let rip. A cacophonous symphony of farts sounded throughout the stadium, and soon enough a cloud of corrosive stink began to form all throughout the arena.

The Mane 6 were all doing their part. Spike and the crusaders were doing their parts. The Princesses were doing their parts. Every mare, stallion, and child in the arena were doing their parts.

A Royal Problem Deleted Scene

As they sat across the royal table from each other eating their pancakes, Starlight had a burning question she had to get from Celestia.

“So, Princess. There’s a little something I’ve been wondering for a while that I’d like to ask.”

Celestia smiled. “Whatever questions you have about royal life I’d be happy to answer, Starlight.”

“OK. Do princesses... fart?”

The room sat silent for a few seconds. Starlight was afraid her question didn’t go over well. That is, until Celestial lifted a leg and ripped one right in front of her.

The smell wafted over to Starlight, who sniffed it in. The stench was foul, more so than she expected.

“Does that answer your question?” Celestial asked.

“More than enough,” Starlight answered.

Vinyl Scratch and Octavia’s Interview
“When we’re alone, Vinyl farts like. An. Animal.”

“Are you sure your colleague is comfortable with you sharing this information?” her interviewer inquired.

“Well...”

The camera cut to Vinyl’s side of the interview, where...

PPPPPPPFFFFFFFFUUUUUUUUUUUUUURRRT!

...Vinyl loudly and proudly lifted a leg and dealt a nasty, deep-pitched fart.

“Ah. Now that was some serious bass, am i right?”

The camera cut back to Octavia’s interview.

“I feel like she won’t mind.”

The Annual Princess Gross-Out [Note: mentions of a lot more gross bodily function stuff than just farting.]
Once a year, the four princesses of Equestria, Celestial, Luna, Cadence, and now newly-christened member Twilight, gather atop the highest spires of Canterlot Castle for a full day in isolation.

Many ponies think this is for something incredibly important, like serious negotiation or even prayer.

This is not true.

You see, the life of a princess is a taxing one. It’s busy and generally speaking you have to keep up some level of public image.

But this isn’t true when princesses are around other princesses. When there’s no pony else around, they can do wherever they please. And in eachother’s presence, they do. When left alone with each other, the princesses can be some of the most unladylike people you ever met.

And once a year, they meet in the highest chambers of Canterlot castle to let their inner wild animals fly.

Because at this event, the princesses be gross. They burp, they fart, they spit, they sneeze out loud, they piss and shit on the floor and wipe their asses on the nicest things they can lay their eyes on, not limited to eachothers’ faces, and they sure as Tartarus don’t bathe.

...And a collection of miscellaneous ideas and concepts and scenes I had written down, usually from dreams or morning jerk-off sessions, that were never intended to become full stories.

Some descriptions/elaboration:

Saving The Stadium

Wherein all the ponies in the stadium must fart and make it stink to high Tartarus to save it from an invasion of an undecided threat.

Vinyl Scratch and Octavia

My idea with these two is that Octavia is usually very resistant to farts and does not do it in public under any circumstances, but Vinyl encourages her to be comfortable doing it around her. Eventually, she is. Meanwhile, Vinyl is generally shameless about gas.

The Annual Princess Grossout

An expansion of the idea mentioned at the end of Twifarts.

And finally, some descriptions for concepts that were never given proper text:

Fartracking

Rainbow and some of her more uncouth friends were bored one day, and decided to pass the time with one of their favorite activities; public farting. Only this time, they concieve of a crowd farting prank that's a little more... musical.

Basically the idea was that Rainbow, Pinkie, and Lyra would go to a club and fart really loudly whenever the music stopped. Vinyl would be involved too, obviously.

Musical Farts

Rarity and Rainbow Dash discover that Fluttershy has a very special talent she had been keeping secret - she can play her flatulence like a musical instrument. Fascinated by this skill, the three try to coax Octavia and her orchestra into playing a show where the main instrument is their friend's gas.

Getting To Know Eachother

Ever since Starlight Glimmer moved to Ponyville, she's been slowly getting to know her mentor Twilight's group of friends.

When hanging out with Rainbow Dash, Starlight discovers she shares some of the lightning-fast mare's tomboyish tendencies...

(...meaning while bonding over milkshakes Rainbow and Starlight discover eachothers’ love of farting.)