WATCH: Popular Group Reunites As Major Wrestling Star Makes AEW Debut

Kyle O'Reilly is officially 'All Elite' and the group formerly known to NXT fans as 'Undisputed Era' appears to have reunited.

O'Reilly made his anticipated All Elite Wrestling debut on Wednesday (December 23) night by helping longtime friend (and rival) Adam Cole defeat Orange Cassidy in the opening match of Dynamite on TNT.

O'Reilly attacked Cassidy while his former reDRagon and Undisputed Era partner Bobby Fish had referee Bryce Remsburg was distracted, leading to Cole hitting his finisher, 'The Boom,' to score the pinfall.

The trio then warded off a response from Cassidy's fellow 'Best Friends' faction members Trent? and Chuck Taylor.

Last week, Cole told fellow 'SuperKliq' members the Young Bucks (Matt and Nick Jackson) that he had "the best Christmas present" lined up for AEW's special 'Holiday Bash' edition of Dynamite, leading to speculation that O'Reilly, whose contract with WWE had expired earlier this month, was set to debut.

Shorty after, O'Reilly tweeted the eyes emoji with a gif of Brad Pitt from the film Seven, in reference to the box Cole was holding while teasing the "gift."

The Bucks, however, didn't seem appreciative of the "gift" as they confronted Cole, who left the ring with O'Reilly and Fish.

After his debut, O'Reilly shared a series of tweets expressing his gratitude for AEW, CEO Tony Khan and confirming that he and Fish would once again use the reDRagon name.

"Life is crazy and I'm very grateful that my professional wrestling abilities have taken me to a new frontier in which to explore my a**-kicking ways," O'Reilly tweeted. "Proud to be apart of @AEW and thanks to @TonyKhan for the opportunity.

"If you're a fan of mine from elsewhere I hope you continue to support me. If you're new to KOR prepare to see a man that pours his f'n soul into that ring every night and has an unquenchable thirst for cans of whoop a**.

"Also, reDRagon is back!!!"

O'Reilly established himself as one of wrestling's best workers competing for numerous promotions, most notably Ring of Honor and New Japan Pro Wrestling, before signing with WWE and debuting on its NXT brand in 2017, as did Fish, although the two initially competed separately in singles matches, despite having gained a legacy as one of wrestling's top tag teams elsewhere.

O'Reilly and Fish first appeared on NXT programming together by attacking then-NXT Tag Team Champions Sanity at NXT TakeOver: Brooklyn III and later newly crowned NXT Champion Drew McIntyre in the show's main event alongside Cole, who made his debut during the attack.