Happy Halloween, everyone! Halloween, the spookiest holiday of the year, fell on a Sunday this year, so celebrities showed off their costumes to their heart's content this weekend. And perhaps to make up for last year's lack of parties, some celebs went all out (although some celebs still got excited at the time (open in new tab)).

While there were obviously a lot of squid games, there were also some serious moments of 90s pop culture. Here are the celebs we thought did it best this year (and, of course, we'll keep you updated as more costumes are revealed):

The "Pretty Little Liars" star dressed up as Cher from "Clueless."

Heidi Klum was not absent when it came to Halloween and decided to forgo her legendary annual Halloween party, but she and her family still had great success with the creative (and genuinely creepy) video.

Rapper Saweetie dressed up as Halle Barry's 2004 Catwoman, and the Oscar winner even made a hilarious cameo in the Instagram reveal.

Harry donned a Dorothy costume on stage when she performed at Madison Square Garden in New York City over Halloween weekend.

Ciara may win Halloween with not one, but two costumes, paying homage to legendary singers Selena and TLC. And check out the "No Scrubs" reenactment video above to see that Ciara is actually Left Eye, Chili, and T-Boz.

Rizzo was so enthusiastic about her Star Wars costume that people stopped her on the street to take pictures with Yoda. They did not notice Rizzo. A new tactic of celebrities hiding in plain sight was unleashed?

Sid Vicious and Nancy Spangen don't want us to see them beautified (the true story of the doomed punk couple is not a happy one (opens in new tab)), but Travis and Courtney deserve credit for working hard on this look.

Bonus points for the comments section below it, where we have no idea who Chloe is supposed to be dressed as.

The couple and their actress friend Olivia DeJonge dressed as Isabella, Paolo, and Lizzie from the movie Lizzie McGuire. And, well, it's a dream come true (opens in new tab). Sing it, Paolo

The Scandal actress went for a Squid Game-inspired tracksuit, but she's not the only one who drew inspiration from the Netflix series. She's not alone:

Members of the K-pop group dressed up as Jisoo as Larisa and Lisa as a Green Light Red Light doll.

Singer Hayley Kiyoko donned a tracksuit for the occasion, calling attention to the fact that everyone was playing the squid game.

Obviously, Meg got a big ovation for dressing up as Cruella, but it was all in the details.

Mrs. Bieber said, "... Baby One More Time" era Britney Spears look-alike.

Fittingly, the Riverdale stars dressed as Velma and Daphne from another classic TV mystery, Scooby-Doo.