As of Wednesday, Dec 1, It's Always Sunny in Philadelphia became the long-running live-action comedy series ever. And as Rob McElhenney said in a recent tweet, "what is wrong with you people?" It's Always Sunny recently premiered its 15th season, in which our gang of idiots and outcasts continue to wreak havoc across Philadelphia, the nation at large, and even a new country this time — Ireland.

After 15 years, it's incredible that It's Always Sunny has maintained its popularity and fresh ideas. As we've aged alongside the gang, the consistency of their stupidity and horribleness is inexplicably heartwarming. Each season, the show proves that it's still just as innovative and original. But where will season 15 stack up in comparison with the high standards set by Always Sunny's previous seasons? We'll set the stage for the new season by ranking all the previous ones. Let's add a qualifier beforehand: every season of It's Always Sunny is funny and original in its own way, but alas there must be those at the bottom and those at the top.

14) Season 1

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Image via FX

Best Episode: "Underage Drinking: A National Concern"

Worst Episode: "The Gang Gets Racist"

Unfortunately, Season 1 must be considered the least impressive of all its seasons. That's not to say it's bad by any means. It's Always Sunny quickly established itself as the most exciting anti-sitcom since Seinfeld . All audiences needed to know about the series they could learn through the first episode, which was called "The Gang Gets Racist."

After years of family sitcoms seeming more like after-school specials, it was great to find a new comedy that lets you know what some of the truly awful people in America think and do. Instead of promoting tolerance and compassion, the first season of It's Always Sunny tackled racism, abortion, underage drinking, cancer, gun control, and sexual assault — all in the worst way possible. While the episodes were not particularly nuanced in comparison to some of their later seasons, they were an enjoyable romp.

It's never a sign of a great television program if the first season is its best. It's Always Sunny was still figuring out its comedy style, how dark they could go, and whether audiences would follow. Additionally, the absence of Danny DeVito's Frank is stark upon re-watching the first season, as he truly rounded out the cast to create the gang we know and love today.

13) Season 13

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Image via FXX

Best Episode: "The Gang Escapes"

Worst Episode: "The Gang Beats Boggs: Ladies Reboot"

Unfortunately, some of It's Always Sunny's latest seasons are low on the list, starting with Season 13. Season 13 is notable for the first appearance of Buff Mac, as well as the absence of Glenn Howerton's Dennis in the first episode. What is commendable about this season is the writers' decision to take risks, to try new concepts that were either hits or misses. Additionally, the season finale of "Mac Finds His Pride" received significant attention, and rightly so, for Mac's beautiful coming-out dance sequence that showcased one of the first times the show took something seriously. And it paid off!

But, the main problem of Season 13 is the way the gang tackled twenty-first-century social politics. Now, our gang has always been particularly politically incorrect for our comedic gain. However, they attempted to continue discussing topical conversations in the same way with more complex issues. This isn't to say they shouldn't have — but it could have been funnier. "The Gang Beats Boggs: Ladies Reboot" is the perfect example, and it might be one of the least enjoyable episodes of the series.

There were also missed opportunities. Several new episodes had great concepts but lacked the execution and humor to pull them off. For example, "Charlie Home Alone" could have been a great bottle episode for Charlie, but it wasn't that entertaining. And "The Gang Does a Clip Show" was an innovative way to do a clip show, but alas didn't make a big impression.

12) Season 14

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Image via FXX

Best Episode: "The Gang Solves Global Warming"

Worst Episode: "Thunder Gun 4: Maximum Cool"

Sadly, Season 14 follows up as one of the lesser seasons of It's Always Sunny because it just was not that memorable. All of the episodes are typically solid, but lacked some of the great quotes and set pieces that made every other season stand out. Season 14's biggest problem was its missed opportunities as well: from bringing back fan-favorite concepts to revolutionary new episodes, the magic just wasn't there.

For example, Season 14 notably brought back "Thunder Gun 4: Maximum Cool" and "Dee Day." While both episodes are good, they lack the originality and memorability of the previous episodes. Additionally, episodes that broke the mold like "The Janitor Always Mops Twice" were funny and cool, but didn't hold a candle to some of It's Always Sunny's more iconic episodes.

11) Season 6

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Image via FX

Best Episode: "A Very Sunny Christmas"

Worst Episode: "The Gang Gets a New Member"

Only three entries into our ranking, we're already to the positively cracking seasons. Season 6 is the season Kaitlin Olsen became pregnant, and her pregnancy was subsequently written into the season. In perfect It's Always Sunny fashion, the other gang members simply do not care, although that doesn't stop a couple of amazing pregnancy episodes ("Who Got Dee Pregnant?" and "Dee Gives Birth") from shaking things up.

Furthermore, the is the first season in our ranking that includes some of the most iconic and classic moments of the series. Mac and Charlie's moms end up living together which will provide moments of hilarity throughout the rest of the series. We also get our first introduction to Maureen and Bill Ponderosa, two recurring characters who become more and more unhinged as one literally becomes a cat and the other delves into hedonistic drug-filled depravity.

And finally, we have It's Always Sunny's first Christmas episode, and it's exactly what fans and audiences would expect. This double-episode special is nearly perfect, punctuated by moments that immediately come to mind like Frank emerging from a couch fully naked, or Charlie angrily screaming covered in the blood of Santa. It's perverse, insane, and exactly how the gang would spend the holidays.

10) Season 11

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Image via FX

Best Episode: "Mac & Dennis Move to the Suburbs"

Worst Episode: "Frank Falls Out the Window"

Next on the list is Season 11, a season that proved the double digits of It's Always Sunny could be just as funny and original as its earlier ones. Most of the episodes double down on what audiences already know and love about the series, including the return of Chardee MacDennis, Dennis' sexual deviance, Frank's baffling lifestyle choices, Charlie's misguided attempts as a lawyer, and, of course, Mac's running gag of his questionable sexuality.

Unlike some of the later seasons, Season 11 didn't take many risks, but it at least featured enough differences and new ideas to make this season worthwhile. We see our gang hit several new locations, including a ski lodge in the hilarious throwback to 80s ski movies "The Gang Hits the Slopes," a cruise ship in "The Gang Goes to Hell," where Mac goes in and out of the closet and Dennis revives "the implication," as well as the suburbs of Philadelphia for "Mac & Dennis Move to the Suburbs."

"Mac & Dennis Move to the Suburbs" may be one of the best episodes of the entire series. It's a hilariously deranged descent into madness a la Stephen King. Mac and Dennis' relationship has always been a highlight of the series, and shining a light on both made this episode stand out. And, all of their triggers are incredibly understandable — the annoyingly cheerful neighbor, the beeping fire alarm, the non-stop traffic, which overall contributes to the monotony of suburban life. It's enough to make anyone go insane.

9) Season 10

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Image via FXX

Best Episode: "The Gang Goes on Family Fight"

Worst Episode: "Mac Kills His Dad"

Season 10 only narrowly beats out Season 11, mostly through the consistency of great episodes and fantastic set pieces. There were misses like "Psycho Pete Returns" or "Ass Kickers United: Mac and Charlie Join a Cult," but every other episode makes the most of its premise. Highlights of this season include "The Gang Group Dates," "Charlie Work," "The Gang Misses the Boat" and "The Gang Goes on Family Fight."

Notably, Charlie Day and Howerton carry Season 10 and helped to make it such a great season. Each of them truly owns one of the episodes listed above, whether it's Dennis' iconic rage speech about his "starter car" or Charlie nailing the obscure answers in Family Fight, only to later realize that he was part of the sample survey. And, of course, the genius behind "Charlie Work" is self-explanatory.

8) Season 2

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Image via FX

Best Episode: "Dennis and Dee Go on Welfare"

Worst Episode: "The Gang Runs for Office"

Coming in around midway in our ranking is Season 2. Early on, It's Always Sunny found its groove and proved that it was a show to be taken (un)seriously. Unafraid to go for the risky joke, Season 2 feels just as fresh as some of the later seasons. Entirely rewatchable, Season 2 showcases our gang at their very worst.

"Charlie Gets Crippled" sees our gang exploiting a disability, "The Gang Goes Jihad" features a myriad of terrorist jokes, "Hundred Dollar Baby" tackles steroids and other drugs, and "The Gang Exploits a Miracle" finds Dee convincing a priest to leave the faith (the first introduction of Cricket!). The best episode of the season is "Dennis and Dee Go on Welfare," which may be the first truly great episode of It's Always Sunny. This episode doubled down on the series' unpredictable humor and separated it from every other sitcom currently airing.

Quitting their jobs and hoping to scam the system, Dennis and Dee go on unemployment and attempt to go on welfare. Based on every other sitcom, we'd expect to learn an important message about why you shouldn't exploit the system. Instead, Dennis and Dee become addicted to crack in a bizarre but hilarious turn of events. And if that wasn't enough, Frank hires new "slave labor" for the bar, while Charlie and Mac procure some escorts that they cannot pay. It's over-the-top but it works, and helped to cement It's Always Sunny as a sitcom to watch (and here we are 15 years later).

7) Season 3

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Image via FX

Best Episode: "The Gang Dances Their Asses Off"

Worst Episode: "The Aluminum Monster vs. Fatty Magoo"

In Season 3, It's Always Sunny doubled down on what made the second season so successful. Raunchy, disturbing but always hilarious, the third season brought audiences more bizarre situations where the gang single-handledly ruins their own lives and the lives of others. Whether it's finding a dumpster baby, setting Sweet Die on fire, or hiding their relationship with a trans woman, the third season proved that our horrible gang could indeed get more terrible.

Part of this season's charm is in its randomness — the seemingly outlandish premises shouldn't work, but for some reason, each episode is just as funny as the last. Additionally, this season brought us the start of many recurring gags that we still see today. We have the McPoyle family, Charlie's illiteracy, and, of course, the first appearance of Charlie's lyrical masterpiece, "Nightman."

6) Season 12

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Image via FXX

Best Episode: "Hero or Hate Crime?"

Worst Episode: "A Cricket's Tale"

The best season in recent years is Season 12, which features a litany of excellent episodes that capitalize on what makes the show great. What makes Season 12 stand out from the previous entries is the quality of writing in almost every episode. With only one exception, "A Cricket's Tale," this season is probably the most consistently good throughout its run.

We've got the gang's musical episode "The Gang Turns Black," a Golden Girls parody in "Old Lady House: A Situation Comedy" and a Making a Murderer parody in "Making Dennis Reynolds a Murderer." Plus, we've got two of the best episodes of the series in this one season: "The Gang Goes to a Water Park" and "Hero or Hate Crime?" The former simply showcases the gang causing shenanigans at a water park, but it displays each character at their most hysterical. And "Hero or Hate Crime?" is a great bottle episode that features Mac sincerely coming out and staying out for the first time!

5) Season 5

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Image via FX

Best Episode: "The Gang Hits the Road"

Worst Episode: "The Great Recession"

Season 5 brought Always Sunny to a new level due to the sheer insanity of referential moments that are still just as funny and inventive today. While the fifth season didn't necessarily push boundaries, it did greatly increase the number of horrible things that the gang does. And, naturally, audiences loved it.

In this season, we see the gang kicking out a family whose house has been foreclosed, entering an apartment that's currently being bug-bombed, trying to make it in wrestling, working on the set of an M. Night Shyamalan movie, and poisoning their rivals during a game of flip cup. And, of course, we have the introduction of the D.E.N.N.I.S. system, an exploration of the crazed and sociopathic behavior of one Dennis Reynolds. And while that episode truly belongs to Dennis, the entire season owes its greatness to Charlie.

And what did Charlie do this season? Well, Charlie ate fruit, pit and sticker and all, he had a nice big box of bees, tried online dating which resulted in lots of cheese eating and sweating, attacked a mascot, created the kitten mittens, and a multitude of other Charlie-isms. Season 5 is Charlie in his most "Wild Card" era.

4) Season 4

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Image via FX

Best Episode: "The Nightman Cometh"

Worst Episode: "The Gang Cracks the Liberty Bell"

As with most It's Always Sunny rankings, Season 4 is normally super high on the list, often sitting in the number one spot. Season 4 proved that It's Always Sunny was just going to keep getting better, and its innovative approach to the sitcom was something that needed to be seen. Even some of the more ridiculous episodes like "Who Pooped the Bed?" are still hysterical, and such a premise could only be pulled off by the incredibly creative team behind the series.

And, most importantly, Season 4 has "The Nightman Cometh." This episode is universally considered the greatest It's Always Sunny episode. The episode was instantly iconic, and now will be forever tied to the series. "The Nightman Cometh" is Charlie's and the series' magnum opus. A slightly frightening but ludicrous musical production, the episode is pure joy and fun. It's the perfect entry into the series for newcomers, as well as a consistent re-watch for die-hard fans.

3) Season 9

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Image via FXX

Best Episode: "The Gang Tries Desperately to Win an Award"

Worst Episode: "The Gang Makes Lethal Weapon 6"

Although this may be considered controversial, Season 9 edges out Season 4 to hold the third spot on the best seasons of It's Always Sunny. Although this season may not have a stand-out episode like Season 4 or a gimmick like pregnant Dee in Season 6, Season 9 stands out because every single episode is instantly recognizable. It's easy to recall the premise, jokes, and plot of each episode, which is a rare feat given the sheer number of It's Always Sunny episodes.

"The Gang Broke Dee" is a great exploration of how far our horrible gang will go, even to each other. "Gun Fever Too: Still Hot" sees our gang tackling personal protection by owning weapons, to naturally entertaining ends. "The Gang Tries Desperately to Win an Award" parodies the tragic fact that It's Always Sunny has never won any major awards and includes Charlie's melancholy spider song. "Mac and Dennis Buy a Timeshare" showcases the stupidity of the gang, underlined by the fact that they think they're being particularly business savvy. Plus, Frank spends the entire episode in a coil on a playground, and we never even get a reason why.

"Mac Day" introduces the senseless concept that each gang member acts as king for a day. "The Gang Gets Quarantined" foreshadowed how much of the country would act during an actual quarantine. "Flowers for Charlie," written by Game of Thrones ' David Benioff and D.B. Weiss, perfectly parodies the novel from which it takes its name, and explores what would happen if the stupidest member, Charlie, became its smartest member.

And the episodes just keep going! I'd certainly recommend a re-watch of Season 9, so that it may become clear that this is indeed one of the absolute best seasons of It's Always Sunny.

2) Season 7

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Image via FXX

Best Episode: (TIE) "The Gang Goes to the Jersey Shore" and "Chardee MacDennis: The Game of Games"

Worst Episode: "Frank's Brother"

The second-best season has got to be Season 7. And this is honestly in part due to Rob McElhenney's commitment to the bit with Fat Mac. While he shouldn't necessarily come back for the sake of McElhenney's health, many more seasons of Mac Fat would have been thoroughly entertaining. The introduction alone lets us know what we're in store for, as Mac attempts to eat and breathe at the same time, wheezing all the while.

But this season is not just great because of Fat Mac — we also see some incredible bits and episodes that are instantly re-watchable. Solid episodes like "Frank's Pretty Woman," "The Storm of the Century" and "The ANTI-Social Network" are pretty great, and who could forget the unforgettable high school reunion episodes, featuring a top-tier dance sequence to George Michael's "Freedom."

But Season 7 also gave two truly perfect episodes. The first is "The Gang Goes to Jersey Shore," which allows each of our gang members to go on their journies through the highs and lows provided by Jersey Shore. Charlie eats sunscreen and hangs out with a high Waitress, Dee and Dennis get themselves caught up in some low-level crime, and Mac and Frank party with the guidos. Plus, rum-ham — enough said, right?

And we also get an introduction to the game of games, Chardee MacDennis. An unhinged game for our unhinged gang, Chardee MacDennis is convoluted, nonsensical, but above all, captivating. Inspiring every friend group to create their own ridiculous game, "Chardee MacDennis: The Game of Games" helped Season 7 achieve legendary status.

1) Season 8

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Image via FXX

Best Episode: "The Gang Gets Analyzed"

Worst Episode: "Charlie's Mom Has Cancer"

Why is Season 8 first on this ranking? Season 8 should be considered the best It's Always Sunny season since almost everyone episode is well-written, well-acted, and just well-done. After Season 3, It's Always Sunny found its comedic mojo, and while some of the later seasons haven't held up as much in comparison, the writing has never been better. What truly makes this season shine, though, is its bottle episodes. It's Always Sunny has always done fantastic bottle episodes, as the hysterical dialogue combined with the terrible characters is all we need for a great episode.

The episodes in question are "The Gang Gets Analyzed," "The Gang Dines Out" and "Reynolds vs. Reynolds: The Cereal Defense." What makes these bottle episodes particularly great is the fact that they succeed off the strength of the character dynamics. Each character within the gang is written so strongly; all of them have identifiable and terrible traits that allow the writers to create such rich episodes. Honestly, It's Always Sunny should be used as a writing template for great characterizations.

Whether the gang gets their idiosyncrasies analyzed by a truly befuddled and horrified psychiatrist, or whether they find out they're all dining separately and speculating on each party, or whether they're debating the legal merit of Frank hitting Dennis's car and causing him to spill cereal, each character shines and brings something in their way. Season 8 is number one on the list because it is It's Always Sunny at its finest.