He landed his first backflip on an ATV in 2006, sparking an around-the-world adventure as the Moore brothers set out with their ATVs to perform on the Crusty Demons and Nuclear Cowboyz tours, among others. By 2012 Caleb was racking up 60,000 frequent-flier miles a year traveling to perform in freestyle shows in locations ranging from Mexico and Costa Rica to Sweden and Russia. Along the way he amassed a list of career injuries to match: a broken back, a torn ACL in his left knee, a broken ankle and broken wrist, and a total of eight concussions, according to ESPN Research. But Moore was undeterred, especially after discovering he could translate his freestyle experience on an ATV quad into a string of podium finishes in the X Games' Snowmobile Freestyle event.
His early successes in the new sport only left him hungrier: After winning three bronze medals and one silver, Moore wanted more. "I wake up every morning, I work out, I try to eat healthier, I'm completely out of party mode. I don't go out," he told X Games Research before this year's event. "I'm strictly focused on trying to reach that holy grail of a gold medal."
Moore's death Thursday, following head and heart injuries sustained during the Snowmobile Freestyle finals Jan. 24 at X Games Aspen 2013, has reopened the debate about the extreme limits of action sports. Moore will be remembered as the first person to land backflips on ATV quads, motorcycles and snowmobiles, but he'll also be remembered as the first fatality in the 18-year history of the X Games.
X Games officials have said they'll be conducting a thorough review of the Snowmobile Freestyle discipline and adopting any appropriate changes to future X Games. Action sports have always been about pushing the limits; Moore pushed them as far as anybody.
"Caleb and his brother were the real deal right from the start: great guys and terrific athletes with amazing showmanship," Australian FMX star Jackson "Jacko" Strong told ESPN.com on Wednesday. Strong and the Moore brothers were Rockstar Energy teammates who first met while performing together on the Crusty Demons tour in Australia. In December Caleb and Colten mentored the X Games Moto X Best Trick two-time gold medalist as he made his own attempt at crossing over from dirt to snow. On Wednesday, before Caleb's death, Strong put the sled he rode at X Games Aspen 2013 up for auction on eBay to help raise funds for Moore's family to pay his medical expenses.
"Everyone knows what could happen before they start riding, and unfortunately this time someone got hurt badly," Strong said before Moore died.
Moore accepted and even embraced the risks of his sport. In 2012 he competed at Winter X Games with a cracked pelvis he'd injured during practice for a freestyle show and a broken tailbone he injured while practicing in Aspen. "When I look at highlights from last year, everything I was doing was completely crooked," he told X Games Research before this year's event. "I was landing crooked, I was getting thrown off and pretty much my whole body was out of whack. I didn't want anyone to know about it. I didn't want anyone to keep me out of the competition."
Caleb Moore is survived by his parents, Wade and Michele, and brother, Colten, 23.
Stunned X Games athletes and other celebrities -- ranging from Tim Tebow to Lil Wayne -- flooded Twitter on Thursday with messages in response to the news. "My deepest condolences to the family of Caleb Moore," wrote former X Games host Sal Masekela. "He was a wonderful kid that loved what he did with all his heart."