It's Always Sunny in Philadelphia recently became the longest-running live-action comedy TV series of all time, and, with a renewal for an additional four seasons, the beloved comedy series isn't going anywhere soon.

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When the dysfunctional, deluded owners of Paddy's Pub aren't singing, inventing, or dodging jail time, they're likely dressed as a Man-Cheetah or an eccentric art dealer. You see, in the world of It's Always Sunny in Philadelphia, you don't have to wait for Halloween to get dressed up.

Ongo Gablogian

its-always-sunny-in-philadelphia-danny-devito
Image via FX

If you need somebody to pretend to be an art dealer, naturally, you'd turn to Frank Reynolds (Danny DeVito), a man who happily lives in squalor and eats cat food. Though he's instructed to be subtle, Ongo Gablogian could literally not be any more flamboyant.

Between complimenting an air conditioner and massively overpaying for a painting, Ongo doesn't quite make the impression the gang hoped for, but he certainly made an impression on us fans. Ongo is an easy yet hilarious costume if you're short on ideas for Halloween.

Crazy Paddy

Crazy Paddy It's Always Sunny In Philadelphia

More than any other It's Always Sunny in Philadelphia character, Dee Reynolds (Kaitlin Olson) loves donning a costume. Across all fifteen seasons, Dee has transformed into an immense variety of colorful and often incredibly offensive characters that only she finds hilarious.

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Crazy Paddy is definitely one of Dee's most memorable characters. The bright red wig is impossible to forget, and her painfully-bad Irish accent and constant stereotyping ensure Crazy Paddy goes down in history as one of the best It's Always Sunny in Philadelphia costumes.

Birds of War

The Gang Wrestles for the Troops
Image via FX

When the gang plans a wrestling event to raise money for the troops, Mac (Rob McElhenney), Charlie (Charlie Day), and Dennis (Glenn Howerton) know that they need costumes worthy of the occasion. Those costumes include cargo shorts, feathers, a yellow beak hat, and drawn-on abs.

Of course, like all great costumes, there's a long and overly-informative song to accompany the outfits, neither of which are much appreciated by the audience. The costumes don't help them much when they come up against Cricket in the ring, but at least they looked good while picking sand out of their eyes.

The Trash Man

The Trash Man Danny DeVito

When the wrestling event goes wrong, there's only one man who can save the day. A man who throws trash cans and eats garbage, finally giving the wrestling crowd the violence and carnage they've been crying out for.

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The Trash Man is an unconventional hero and one the gang is quick to dismiss, but as is often the case, Frank Reynolds is right. His costume may be ill-fitting, and his approach may be brash, but The Trash Man is the hero Philadelphia needed, and we fans are desperate to see him make his long-awaited return to the ring.

Psycho Clown Killer

Mac Is a Serial Killer
Image via FX

Only Dennis and Dee could go from investigating a string of local murders to quickly envision themselves committing those murders and donning the costumes their serial killer alter egos would wear. While Dennis' outfit is more practical, Dee opts for a "psycho clown" outfit that doesn't exactly blend in with her surroundings.

Naturally, the brother-sister team decides to test their hypothetical murder plan on the waitress (Mary Elizabeth Ellis) and get far too wrapped up in the scenario before Dee's squeaky clown shoes startle the waitress. She blasts them both with pepper spray. The outcome they deserved to be frank.

The Nightman

The gang performing The Nightman Cometh on stage in It's Always Sunny in Philadelphia.
Image via FX

No musical could ever be as chaotically perfect as The Nightman Cometh, and no musical character could ever be as iconic as The Nightman. Though Charlie originally wanted Dennis to play the role, Mac steals the part for himself and very quickly makes it his own.

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As he does with most things in his life, Mac finds a way to work karate into his performance, unleashing various moves each time he crosses the stage, much to the audience's amusement. He also wears cat eyes (because, of course, Frank has a guy for that) and forgets most of his lines. His performance is by no means good, but it's one that will go down in history.

Electric Dream Machine

Charlie Day and Glenn Howerton singing on stage in it's always sunny in philadelphia
Image via FX

After being kicked out of Frank and Mac's band Chemical Toilet, Charlie teams up with Dennis to create a new band that heads in a very different direction. Electric Dream Machine is a unique band that, in the words of Dennis Reynolds himself, offers the audience the chance to experience sexual magic.

Their shiny outfits, outlandish wigs, and upsettingly high-pitched vocals cause the audience to quickly turn on the band, who unfortunately don't even manage to finish a song before being jeered off-stage—shame on you, audience.

Honey and Vinegar

Hank Honey and Vic Vinegar

Honey and Vinegar are partners in real estate and partners in life. They are also the last people in the world that you would want to buy a house from, but that doesn't stop them from trying their damn best.

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Wearing matching mustard-colored blazers and taking the good cop, bad cop approach to sales, Honey and Vinegar quickly sell their first house by threatening the potential buyers. Of course, the sale does not stick, and Honey and Vinegar dissolve as partners in real estate. Vic Vinegar does later return as a bodyguard, though, having even less success in that role than he did in real estate.

Man-Cheetah

Man-Cheetah Danny DeVito It's Always Sunny In Philadelphia

When the gang falls out, Frank heads in search of a new crew. Unfortunately for that poor unsuspecting group, they have no idea how much damage Frank can do to their new bar in just one night. This means they're not too happy to see him return dressed as a Man-Cheetah the next day when they're dealing with the closure of their bar.

Upon returning to Paddy's Pub, though, the gang remembers why they were such good friends in the first place, mainly because they all love Frank's costume and are excited to work it into a scheme. That is, if Frank has enough spots for all of them.

Man-Spider

Man-Spider Danny DeVito It's Always Sunny In Philadelphia

Frank Reynolds wants it known that he didn't go to the Paddy's Pub Halloween party dressed as Spider-Man; he went dressed as Man-Spider. Instead of wearing a cheap imitation superhero suit, he is dressed as a human-sized spider. Sure, most people would instead go dressed as Tom Holland's web-slinging superhero, but Frank is no ordinary man.

The black and red costume seems to be a hit with his booty call Artemis, though, although their food-related adventures are something nobody wants to think about.

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