FicFan.org

And on the balcony of the Palace, standing tall and arrogant, was King Sombra himself.  His mane, tail, mustache, and cape were flapping dramatically in the wind as his crown glinted from the few rays of sunlight that managed to break through the clouds.  Flanking him on either side were Celestia and Luna, helmets suckered on their heads, acting as bodyguards.  With a cold, borderline serpentine eye, Sombra looked over the assem-

Wait.  Sombra had a mustache?

Twilight looked again.  It wasn’t just a mustache, it was the handlebar mustache to end all handlebar mustaches, beyond compare of any before or any to come.  It was impeccably groomed, with not a hair out of place, a glossy sheen coating it, and ends that turned up in just the right ways.  Quite possibly one of the biggest, curliest, most fabulous mustaches Twilight had ever seen, it seemed purpose-built for twirling while cackling villainously.

And twirl it while cackling villainously Sombra did.  “Yeeeeeesssssss,” he said, rubbing his hooves in between twirling his mustache.  “With this unstoppable army at my command, with even the Princesses themselves under my hoof, all of Equestria shall be mine!  Mwa ha ha ha haaaaaa!”  He wasn’t even properly cackling, Twilight realized; he was clearly enunciating “mwa ha ha”.

Twilight gave a sidelong glance at Luna.  “I’m… not sure this is quite as dire as it seems.”

Luna stared at Sombra slightly slack-jawed.  Or, to be more precise, at Sombra’s spectacular mustache.  “…No.  Perhaps not.”

https://www.fimfiction.net/story/316104/2/tantabus-mk-ii/error-is-reproducible