NASHVILLE -- Ethan McClean thought he was going on a hunt for Bigfoot in the Tennessee mountains. At least, that's the destination his parents, Andy and Yvette McClean, gave him as they loaded his wheelchair into the rental car on Monday.

But instead of a Sasquatch, Ethan found himself being greeted by a saber-tooth tiger wearing a Nashville Predators jersey in front of a hockey arena in Nashville. That's where a 10-year-old fan from Ballymena, Northern Ireland, diagnosed with a terminal illness, watched his first NHL game on Monday evening in the last stop on a remarkable hockey adventure.

"The muscles in his face are starting to deteriorate," Andy McClean said. "But we're seeing smiles this week that we haven't seen in a long, long time."

Eighteen months after he was born, Ethan was diagnosed with Duchenne muscular dystrophy, a disorder that is wasting away his muscles. Within the next 18 months, he'll lose use of parts of his legs. Then his arms will go. Then the rest of his muscles. His life expectancy is roughly to his mid- or late teens.

"He's on his feet today," Andy said. "It's the adrenaline from being here. This is what's keeping him on his feet."

After the Predators' mascot, Gnash, met him, Ethan assumed that was the extent of his visit to Nashville.

"An NHL game is too expensive for us, isn't it daddy?" he said through a disarming Irish lilt.

The disease makes the muscles in his bladder weak, so he must make frequent bathroom stops. So it was suggested that, perhaps, Ethan could use the bathroom in the arena. And then, perhaps, they could stay there and watch the Predators and the Tampa Bay Lightning that night.

"Do you think we can stay for the game?" Andy asked.

"What? WHAT?!" Ethan responded.

With that, the family entered the building to catch the Predators' morning skate. Gnash pushed Ethan in a chair adorned with Captain America's shield on both of its wheels.

Ethan's hockey adventure in America actually began with his love of that Marvel Comics icon. "Ethan is an absolute avid Captain America fan," Andy said.

Last year, the Atlanta Gladiators of the ECHL had a Marvel Comics night and wore Captain America novelty jerseys that were to be auctioned off after the game. Joel Neill, whom the McCleans knew through Ethan's favorite hockey team in Ireland -- the Elite Ice Hockey League's Belfast Giants -- made the ask for the young fan over Twitter:

Hey @atlgladiators have you met the @BelfastGiants biggest fan Ethan @team_mcclean? He's a v special wee dude and Captain America has helped to give him a tonne of courage and fight.



What do we need to do to get him one of those Marvel jerseys? 🙏🏻@ECHL pic.twitter.com/cXgSbdtK20 - Joel Neill (@joelneill) December 1, 2017

Ethan was sent a jersey by the Gladiators, and so began a long-distance relationship between the team and the young fan's family. The team helped him when he arrived in America. But he relied on his own local hockey community to make the trip possible.

The U.K. Charity All-Stars is an annual weekend hockey event that raises money for several causes. A player named Geraint Walters was supporting an organization called Dreams Come True and was enamored with Ethan's story. (The young fan had a high profile in the EIHL, having been embraced by the Giants through the years as their No. 1 fan.) The charity decided to make Ethan's dream come true: Pay for his family to fly to Atlanta this month and watch the Gladiators play three home games.

"He put his trust in the Glads. I made it my mission to give him the greatest trip ever," said Chris Treft, director of communications and broadcasting for the Gladiators.

The family arrived on Monday. On their first evening in the U.S., the Gladiators were on a road trip, so the team arranged for Ethan to watch their game in the locker room with some of the team's injured players. Then they invited him to practices. They invited him to games. They sat him on the bench. They took him to Dave & Busters. He announced their starting lineup. And on Friday, the Gladiators even had him meet Captain America himself before the game, on the ice:

What's better than dropping the ceremonial first puck to start your #DreamsComeTrue weekend? Doing it with your favorite Super Hero! pic.twitter.com/dnHodfgr8y - Atlanta Gladiators (@atlgladiators) November 17, 2018

On Sunday, Ethan watched his last Gladiators game in Atlanta.

"He was crying. He thought it was over. And it was impossible not to cry with him," Treft said.

But it turns out that it wasn't over. It was on to Nashville the next day, a trip arranged by the Gladiators, who have a working relationship with the Predators.

"I told them we had this kid coming over from Ireland. He picked us as his favorite team. But we think it would be even better if he could see an NHL team. And they said, no problem," Treft said.

Ethan watched the morning skate in the 100 section with Gnash before moving down to the glass, his wheelchair parked in the Zamboni entrance. He collected a stick from Predators defenseman Matt Irwin after practice, which Irwin slid to Ethan through a hole in the glass. It is one of an increasing number of sticks, pucks and jerseys Ethan has collected on the trip.

But all the memorabilia in the building can't equal those moments Ethan had with his hockey heroes. Take, for example, a surprise meeting with Predators star P.K. Subban in the Nashville dressing room.

"Is that like the Captain America [shield]? My girlfriend, Lindsay, she skis. She has a suit with the same symbol on it," said Subban, referencing significant other Lindsay Vonn as he pointed at Ethan's chair. Ethan leaned over and lit up his sneakers by pressing a button.

"Wow, nice kicks," Subban said. "Holy smokes."

Ethan watched the game that night as a guest of the Predators, wearing a personalized Nashville jersey and sitting with his parents. The Nashville fans were honored to meet him, with one gifting him a lucky scarf he had worn to home games for 10 straight seasons.

It'll join an impressive collection of hockey trinkets in Ethan's room back in Ballymena. His father said they had to create a new first-floor room for Ethan, as he couldn't easily make it up and down the stairs any longer. There are pucks and jerseys and sticks and bobblehead dolls, collected in a variety of ways, including requests to teams made through the family's Twitter feed dedicated to their son, Team McClean.

Teams from around the world are represented, including Ethan's favorites -- the Belfast Giants, Atlanta Gladiators and now the Predators -- as well as his favorite player, Sidney Crosby of the Pittsburgh Penguins. "Hockey is his life," Andy said. "You know, he has a lot of frustration built up about things he can't do that his peers can do. But you see him at an ice hockey game, and he's shouting and chirping. He'll hurl abuse at people. Bang the glass. He does it all there."

Ethan McClean and Yvette McClean got the hockey trip of a lifetime. Greg Wyshynski/ESPN.com

For a week in America, he did it all, too, including cranking the siren before the third period at the Predators game on Monday night and receiving a loud ovation from the crowd. He also won "fan of the game" through a crowd vote, which earned him free pizza and earned the crowd a thumbs-up from him as he sat in his wheelchair in Section 101.

Were you surprised when they took you to your first NHL game, Ethan?

"Yes," he told ESPN while standing near the glass in Nashville.

What was your favorite thing today?

He smiled one of his increasingly rare smiles.

"Watchin' the ice hockey," he said.