Since 2009, RuPaul Charles and his queens have been absolutely slaying the reality TV show game. We are currently right in the middle of a sickening 12th season, eager to see who is going to walk away with the crown and $100,000 prize. If we include All Stars, which we obviously do, we've seen 15 queens crowned already. While each winner has brought their own set of skills to the race, they're not the only ones who have us gagging week after week.

Mama Ru, Michelle Visage, Ross Mathews, and Carson Crestley are always fantastic and many fans simply tune in each week to see which queens are the fakest of the bunch. However, one of the major bonuses fans of Drag Race get is the never-ending parade of celebrities who show up to guest judge. We were living for Nicki Minaj's appearance this season, but which other celebs have been around that we've forgotten about at this point?

15 Khloe Kardashian Should Be A Regular

Anyone who's ever watched Keeping Up with the Kardashians knows that Khloe is the funniest of the clan (the bar really isn't all that high). However, her turn as a guest judge in two separate episodes of season 6 had us wanting more. With no filter, she fit right into the panel.

14 Michelle Visage HATED Joel McHale

While Tiffany Pollard was in fact there as well during Joel's season 11 appearance, it was his beef with Michelle Visage that really won the episode. Sorry, it would be better to call it Michelle's beef with him. His loud, obnoxious remarks and screeches every time a queen stepped out had Michelle itching to slap him.

13 Baby Spice Is Back!

Sorry, not sorry Adam Lambert, but you picked the wrong episode to appear on. While Lambert is a fairly logical choice for a Drag Race guest judge, we were absolutely living for Emma Bunton in their season 3 episode. Honestly, it was just so nice to see Baby Spice doing something other than Prego tomato sauce commercials.

12 Mitch But No Cam?!

Heading all the way back to season 4 episode 10, Modern Family's Jesse Tyler Ferguson stepped up to give his two cents. He was accompanied by Jennifer Love Hewitt and as adorable as she always is, we do wish Ru would have been able to score his on-screen husband, Eric Stonestreet.

11 Clinton Always Knows What To Wear

Clinton Kelly was brought on to judge season 5's 10th episode and we were GAGGING. Even though he did not have the sassy Stacey London as a co-star this time, we still love the guy and it was just so nice to see him away from the crazy world that is TLC.

10 Demi Was In The Wrong Episode

Demi Lovato was a guest judge on season 7's 9th episode. There's no denying she's a massive star so having her show up at all is pretty impressive on Ru's part. However, we can't help but to wish she had been there during Brooklyn and Yvie's iconic season 11 lip sync to Lovato's Sorry Not Sorry.

9 Jessica Alba Is Always A Welcome Sight

Jessica Alba gave us everything we could have expected from her during her season 7 appearance. She is cute, fashion savvy, and just an all around pumpkin. That being said, she delivered kind critiques to each queen, keeping her reputation as Hollywood's Sweetheart totally intact. No drama to be found here!

Related: 20 True Facts About The REAL RuPaul Charles

8 We'd Love To See Leah Remini Return

Leah Remini's guest spot in season 6 was everything! She and Michelle Visage go way back to their days in Jersey and their chemistry was a blast to watch. They delivered excellent banter, leading Mama Ru to even state how she shouldn't have agreed to let them sit together. Hilarious!

7 Cersei Came To Slay

That's right, the once-Queen of Westeros popped up on Drag Race way back in season 6. Now, Drag Race queens have often compared themselves to GoT characters, so this really was a fun pick for a guest judge. However, we can't help but to wish she had been around for one of Shangela's (many) seasons.

6 Not Grace, Not Frankie, But Lily Tomlin!

Being able to score Hollywood legends like Lily Tomlin really just goes to show how respected RuPaul is in the industry. Tomlin appeared in season 3 episode 3, but we're thinking it's time for her to make a come back, this time maybe even with Jane Fonda in tow (fingers crossed!).

Related: 15 Sweet Photos Of RuPaul And Michelle Visage's Friendship