Fans of How I Met Your Mother are finally getting the well-talked about spin-off series, How I Met Your Father, starring Hilary Duff. Not much has been revealed about the series despite it premiering on Hulu this January. Nonetheless, fans can hope it'll be as legendary as the original. Seeing as both series coexist in the same universe, maybe fans will get to see their favorite celebrity guests reprise their roles.

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How I Met Your Mother is famous for having numerous a-list celebrates guest stars, some of which became fan favorites despite many of them only appearing for one episode. How these guests became such memorable characters has to do with their impact on the episode or series as a whole.

Regis Philbin

Regis Philbin threatening Barney in HIMYM

"The Best Burger in New York" is one of those episodes that fans will always remember, and it wouldn't have been complete without Regis Philbin. In this episode, Marshall has been down on himself about not finding a job. His frustration has forced him to pour his focus into something else, manifesting into finding the "best" burger in New York.

Philbin's character supports this frustration seeing as he too is hung up on the burger. He adds the needed humor in this episode as it does take on the deeper topic of self-doubt. His memorable threatening demeanor is a stark contrast from his actual personality. When Philbin sadly passed away in 2020, Josh Radnor took to social media, showering the TV icon with praise.

The Blitz

The Blitz looking into the distance in HIMYM

"Blitzgiving" has to be one of the most unforgettable episodes of its entire season. Jorge Garcia guest stars as The Blitz or Steve, one of the best characters introduced into the show. The Blitz is Ted and Marshall's "cursed" college friend and due to the curse, he misses out on every amazing event that ever happens, spawning the famous phrase, "Aw man!".

His character made this episode light, funny, and a must-see when fans re-watch the series. His not-so-subtle references to his character on the show Lost make for some hilarious laughs. The Blitz does make a cameo in the final season. where it's noted the curse is still with him, when he just misses out on winning the jackpot in Las Vegas.

Honey

Hoeny at the bar smiling in HIMYM

Katy Perry plays Zoey's gullible cousin in "Oh Honey". Due to her gullible personality, the gang only refers to her as Honey, but mainly because they've forgotten her name over time. Honey and Ted are set up by Zoey in an attempt for Zoey to get rid of her feelings for Ted.

Honey is remembered for having played a role in setting up Zoey and Ted, which becomes one of Ted's more serious relationships in the series. But she is mainly iconic for her hilarious stories in which she was the unknowing victim. These stories played into her gullible and naïve personality and structured most of the comedy of the episode.

Maury Povich

Maury Povich at the subway in HIMYM

The How I Met Your Mother cast competes yet again in "Subway Wars", during which Robin feels that New York is rejecting her. Adding fuel to her already pent-up emotions, the group states she's not "a real New Yorker" just because she's  only seen Maury Povich, as he is the one celebrity that everyone sees in New York.

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Maury appears more than once and in multiple places at the same time, further adding to the hilariousness of the joke, he soon becomes the most anticipated character to see in this episode. "Subway Wars" explores the characters' main frustrations at the time and Povich adds some much-needed humor, lightening the episode. It would be a great addition, if the spin-off series, gave Povich a cameo, just to keep the joke going.

Anita

Anita gets flirty with Barney at the bar in How I Met Your Mother

Anita, played by Jennifer Lopez, is a famous author of a self-help book for single women. In the episode, Robin has Anita teach Barney a lesson about treating women better, after his inconsiderate behavior since their breakup. Barney and Robin's relationship tackled deeper issues relating to toxic relationships, which in the end made Anita's impact on Barney that much more powerful.

Although her scheme does not go as originally planned, she does make fans realize that Barney is a better man than he pretends to be. Anita is memorable for her hilarious ability to make men do her bidding, all with the power of the word "no". Lopez was already an accomplished actor at the time of her appearance and proved her skills by playing the part of Anita so well.

Fake Moby

Fake Moby and Barney in HIMYM

Moby was a popular recording artist from when Ted was younger. Only the Moby the gang meets during New Year's Eve of 2005 is not the real Moby. Fake Moby (J.P. Manoux) was memorable to not only the gang but also the fans.

His erratic behavior and personality have been engraved in fans' minds, seeing as his character was even referenced in an episode of Community. If Fake Moby were to make an appearance in the spin-off, it would be epic. But this is most likely not to occur, seeing as Hilary Duff's character is a different age than Ted and may not know who Moby is.

Ralph Macchio

Ralph Maccio talking to Barney in HIMYM

Ralph Macchio plays himself in the episode "The Bro Mitzvah". He plays a part in Robin's plan to give Barney the worst bachelor party, which ironically is one of the most romantic gestures Robin's made on the show.

The uncanny similarities in Ralph and Barney's personalities make for some hilarious banter between the two. Seeing another Barney on screen may not have played out as many fans expected but was definitely worth it. Macchio no doubt plays the antagonist in this episode, despite being the hero in his most famous role, the Karate Kid. This disparity creates some amusing dynamics to occur within the cast, like Lily's overly flirtatious actions towards him.

Royce

Royce laughing while at the movies with an exasperated Ted in HIMYM

Royce is dating Ted at the time of the episode "The Wedding Bride". Ted mentions dating being hard because everyone comes with "baggage" and once that baggage is revealed he tends to end the relationship. Upon seeing the new movie, "The Wedding Bride", a movie about Ted's romance with Stella, he realizes he's the one with baggage. At the end of the episode, Ted tells Royce to leave his apartment after hearing what her baggage is.

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Royce is not mentioned again in the series, seeing as their relationship did not end well, but "The Wedding Bride" is. It's mentioned as being a hit Broadway musical in "Vesuvius", and has a third installment hinted to in the background of the beginning of, "No Pressure". Fans would no doubt be enthusiastic if the movie were mentioned in the spin-off. Even if it doesn't connect to How I Met Your Mother with a cameo, it would be a great reference to the show, and to Royce, the one who lead Ted to see the movie.

Gus

Gus at the bus looking annoyed in How I Met Your Mother

"Bedtime Stories" is an unforgettable episode because everyone speaks in rhyme throughout its duration, although some fans probably forgot that Lin-Manuel Miranda guest starred in it. Since Marshall is riding a bus with his infant son at the time, he has himself, as well as everyone else, speak in rhyme so his son can fall asleep more easily.

What's truly amazing is the mini-performance given by Lin-Manuel Miranda who plays Gus, just another passenger aboard the bus. He raps an impromptu verse easily rhyming the word "Canada". Although Miranda's appearance may have seemed odd due to him not being well known by fans back then, he was an excellent choice for this episode.

Blah Blah

Blah Blah talking to Ted in HIMYM

Although the gang may not remember her name, fans do. Abigail Spencer's character Blah Blah made quite the first impression on the group. Her first meeting with the group ended up with Ted telling the story of how he met everyone else.

Her appearance is not forgotten as she is mentioned a couple of times in later seasons. Lily mentions that she has been committed to Bellevue Hospital. This may be the reason she was not brought back for another full episode aside from her relationship with Ted breaking apart dramatically. She is also mentioned in "Gary Blauman" when Ted finally recalls her name as Carol.

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