Both Monsters Inc. and Monsters University have been deemed two of Pixar's very best films. With the launch of Disney+, The Walt Disney Company was keen to return to the established world. This has resulted in a combination of returning and brand new characters for audiences to enjoy each week, but not all of the fan favorites have made an appearance thus far.

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While there are classic characters that have already proven to be mainstays of the Monsters At Work series, there's still a variety of heroes and villains from the two original feature films which are yet to make an impact in the sequel show. There are clear narrative reasons for these absences, but that doesn't mean these monsters can't return in the near future!

Confirmed For The Show: Mike Wazowski

Mike Wazowski performs his comedic routine inside a kids bedroom on a wooden chair

One of the key characters in the franchise, fans have tracked Mike from his days at Monsters University in the well-received prequel/sequel, all the way to the Scream Floor. With best friend Sully along for the ride, Mike's days as an assistant are over as he paves a new path for Monsters Incorporated.

Now at the top of the mountain, Mike's comedy routines get the big laughs needed to power Monstropolis. Fans were desperate to see Mike's story continue and Monsters At Work does a great job of adding to his narrative while giving the new characters room to develop in their own right.

Fans Want To See: Randall Boggs

Randall gives an evil stare in the changing rooms of Monsters Incorporated

Randall has also appeared in both Monsters University and Monsters Inc. but has yet to make a reappearance in Monsters At Work. Fans last saw the character getting arrested for his crimes against both his colleagues and the kids he was tasked with scaring.

With Randall taken out of the story for now there's no telling if he will return in the future. Randall is perhaps one of Pixar's most underrated characters though as fans really do love to hate him. He's the perfect villain and would be an intriguing addition to the show if further conflict is needed.

Confirmed For The Show: James P. Sullivan

Sully and Mike with Boo in Monsters Inc.

Sully has dreamed of picking up his father's mantle as a scarer all his life. Yet he also aided Mike in dismantling the Monsters Inc. system after previously working to the top from the Mail Room. Sully is now CEO of the company and is making huge changes to move from screams to laughter.

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Much like Mike he has already made an impact in the series. His veteran experience makes Sully slightly better than Mike in terms of his leadership qualities, but Mike is really the brains behind the operation. Sully continues to be a charismatic presence though and a reassuring figure that the other monsters can rely on.

Fans Want To See: The Abominable Snowman

The Abominable Snowman presents his lemon snow cones in his ice cave

Making only a brief cameo in Monsters Inc. the Abominable Snowman is one of the few monsters who has been exiled from the parallel reality and sent to live with the humans. The Snowman largely loves his new home though and seems to still keep in contact with his friend Big Foot.

With the Abominable Snowman still living in the human world, it's unlikely he'll show up in the series. However, with the Laugh Floor now returning to old locations to potentially find new sources of energy, it's plausible that the Snowman could make a reappearance as a great snow cone-making addition to Monsters Inc. What's more one of the things most Pixar films have in common is the legendary voice of the Snowman, John Ratzenberger!

Confirmed For The Show: Roz

Roz gives a disgruntled look from behind her desk, while wearing her glasses

An absolute fan favorite, Roz provided some of Monsters Inc's. funniest moments. Disguised as an administrator, Roz was actually the leader of the Child Detection Agency or the CDA. She made a brief cameo in Monsters University in the role but now her cover is blown.

Roz returns for the debut episode of Monsters At Work but must return to her true role as Number 1 in the CDA. She has luckily left her relative in charge of proceedings with twin sister Roze instead acting as administrator. Fans can still get some of that trademark dry humor and grating voice.

Fans Want To See: Henry J. Waternoose III

Mr Waternoose on his coffee break in Monsters Inc

Henry J. Waternoose III is a significant member of the Monsters Incorporated structure. The company has been in the monster's family for generations, but his desperation grew the best of him as he continued to look to exploit the screams of children across the globe.

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Monsters Inc. ends with the character getting arrested for his crimes, although there's always a chance that he could be plotting his vengeance. It would be interesting to see Monsters At Work catch up with Waternoose, especially since his beloved protegee has now taken over the company he sacrificed everything for.

Confirmed For The Show: Celia

Mike smooth talks Celia at her work station as Sully looks away

Celia is Mike's girlfriend, receptionist, and calls operator in Monsters Inc. While not appearing in Monsters University she would have likely been a major part of the canceled original sequel and is now the Laugh Floor manager at Monsters Incorporated.

Still a huge factor in Mike's life, there are already teases that the duo may be thinking about starting a family together. Celia has adapted well to her more authoritative role though and is sure to be an important component in the success of the Laugh Floor as it continues to evolve.

Fans Want To See: Oozma Kappa

Mike challenges his Oozma Kappa brethren outside of their fraternity house

Oozma Kappa was the fraternity that Mike and Sully were forced to join in Monsters University. The group became lifelong friends but it's unclear what happened to them after their adventures. The last fans saw, the group were enrolled to study to be scarers at MU.

Oozma Kappa would probably make perfect jokesters so fans are eager to see them potentially return in a new role. Audiences have seen Mike and Sully grow up across multiple projects and it would be an important beat to see the fraternity do the very same. Indeed, in their own right Art and the rest of Oozma Kappa are incredibly underrated.

Confirmed For The Show: Fungus

Fungus is berated by Randall on the scare floor of Monsters Incorporated

Fungus was Randall's right-hand man in Monsters Inc. aiding him in some of his nefarious plans. Clearly manipulated by the scarier monster though, Fungus has since tried to live an honest life. He returns in Monsters At Work in a very similar role.

Now an assistant to Mike, he continues to operate on the Laugh Floor, hoping to redeem himself for his past actions. Although he's never been a fan favorite per-say, Fungus is a crucial part of Monsters Inc. lore and shows Disney's dedication to continuity in the franchise.

Fans Want To See: Boo

Boo reaches out for a hug in Mike and Sully's apartment

Boo may be one of Pixar's most celebrated and greatest heroes in all of their movies. She immediately captured the hearts of audiences and escaped into the world of monsters. She faced down her fears by defeating Randall and was left in the human world to live out her life again.

It was a bittersweet and emotional ending, but fans know that Sully has the door needed to return to Boo's room if he so wishes. With Mike and Sully now in control, it's plausible that they make a decision to return to Boo's world again and spend a little bit more time with their favorite child.

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