Stephen 'tWitch' Boss was found dead at a hotel in Los Angeles on Tuesday. He was 40. His death has been ruled a suicide.

Boss, who was known for co-hosting "The Ellen DeGeneres Show," had been a regular on the reality show "So You Think You Can Dance" since 2007.

While he started his journey as a contestant, he eventually became a judge on the dance reality show. Let's have a look at some of his most memorable dance performances over the years.

Mercy

Boss performed "Mercy" with choreographer Mia Michaels on Season 4 of "So You Think You Can Dance" in 2008. Boss kissed Michaels during their performance and revealed how they didn't do any rehearsals.

"During that kiss, we hit each other's teeth so hard because we didn't rehearse before," he said at the time, People reported. "I liked that routine a lot."

Outta Your Mind

Here's another performance of Boss with Alex Wong from Season 7. In a reaction video in October, Boss shared that it was one of Wong's "proudest" performances.

Boss also explained that it "could've gone down really badly," considering Wong was a ballet dancer and the routine (hip-hop) was new for him.

First Audition

Boss' first audition on "So You Think You Can Dance" happened in Season 3, which will always remain special for his fans. Many fans revisited the audition video on YouTube following the dancer's tragic death, just to praise his talent once again.

Dreaming with a Broken Heart

One of Boss' best performances, "Dreaming with a Broken Heart," started trending on social media Tuesday. The routine was performed with Kherington Payne on Season 4 of the reality show.

"It's a lot to get over, I don't dance in bare feet," Boss said while reacting to the performance in June. "But I'm not going to lie, this is one of those routines that I'll remember forever. I was talking about textbook moments for So You Think couples, and Kherington really helped me out with this one a lot and really helped ease a lot of my insecurities around this, too."

The Ellen DeGeneres Show

Aside from Boss' performances on "So You Think You Can Dance," he also danced to entertain the audience on "The Ellen DeGeneres Show." He was a regular on the show since 2012. Here's a compilation of his best moments on the talk show.

Aside from dancing, Boss can also be seen having fun conversations with host Ellen DeGeneres and sharing his passion for dance.

Stephen "tWitch" Boss
Stephen "tWitch" Boss on the Ellen Degeneres Show Mike Rozman/Getty Images