Yes, Halloween has sadly come and gone. But, that doesn't mean we can't take a look back at the most hilarious costumes the celebrity world had to offer this year.

The Kardashians weren't the only ones that leveled up this Halloween.

Everyone knows spooky season is also good for a laugh, and some celebrities got super creative for Halloween this year, cracking everyone up for with their costumes.

The effort level was at an all-time high as the stars up the ante and really thought outside the box with their epic looks.

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From recreating unforgettable memes to walking streets dressed as baby Yoda, here are the top four celebrity costumes for 2021.

Steve Buscemi spent Halloween in Brooklyn, where he handed out candy to trick r' treaters.

But, fans were in for more than just sweets when they saw him.

The actor actually showed up as his own comical 30 Rock character, the dimwitted Detective Lenny Wosniak.

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Buscemi's fictional counterpart was so memorable that it became a viral meme, used to poke fun at anyone who is trying – and failing – at getting with the times, à la his famous "How do you do, fellow kids?" line.

On Sunday, the 63-year-old wore the iconic red hoodie, matching-backward ball cap, complete with a skateboard, while posing for pics with fans.

The following day, the Buscemi's costume became the most trending topic, as lucky users who came across him shared their snaps.

Lizzo went all out this year with no less than three different costumes.

For her Grogu, aka Baby Yoda costume, the Coconut Oil singer was covered from head to toe in mint-green body paint.

Taking a page out of Heidi Kulm's book, she sported matching-prosthetic ears on each side of her head with a long blonde wig.

The singer strolled the streets of Hollywood disguised as The Mandalorian character, though fans eventually figured out it was her.

On Monday, the Truth Hurts artist also shared pics of herself completely covered in an all-black one piece ensemble similar to Kim Kardashian's Met Gala outfit.

Then there was her impression of Dorothea from the 1992 cartoon Bébé's Kids. Hands down, Lizzo definitely brought the heat this year.

Harry Styles paid tribute to an iconic figure during his two-part Halloween-themed shows at Madison Square Garden.

The singer dazzled fans with his rendition of Somewhere Over the Rainbow and took the stage in Dorothy Gale attire.

The 27-year-old star wore a blue and white dress similar to one Judy Garland famously donned in The Wizard of Oz.

Harry topped off the outfit with red tights, a stunning hair bow – and pf course, a pair of ruby red Gucci slippers.

And yes, Toto made an appearance too, albeit through a fake dog.

This year, the supermodel couldn't have her yearly haunted bash.

Regardless, Heidi proved that she will always be the queen of Halloween.

She's known for her dedication to the holiday with her bizarre, yet iconic looks. This time was no different, as the America's Got Talent judge aptly delivered again this year.

For 2021, the 48-year-old tapped into her inner feline, and transformed into a stunning red-haired cat-like monster.

For her look, she sported a face covered in paint and a sexy, black leotard-style ensemble with fur lining, headdress, furry tail, and a plunging neckline.

And what is a cat without a mouse to chase around?

Heidi's husband, Tom Kaulitz, joined in on the fun with his wife as a brown mouse with a straw hat and pointed teeth.

All hail Halloween queen Heidi!