A modern day Dr. Doolittle who calls the cats his "children," Horn has spent vast amounts of time, energy and money on animals who have left millions of show-goers here in awe since 1966.
The menagerie developed by Horn and longtime stage partner Siegfried Fischbacher includes 63 rare white tigers and white lions. Horn has been on hand for many of their births.
"The first voice they hear is mine, the first touch they feel is mine, the first human face they see is mine," Horn said in an interview in late 2000. "They just think I'm a strange tiger who walks on two legs."
But on Friday night, just 20 hours after Horn had celebrated his 59th birthday with hundreds of friends, one of the beasts inexplicably turned on him at the Mirage hotel-casino.
As he had done thousands of times, Horn sauntered onto the stage with 7-year-old Montecore, a white tiger who has appeared in the show since he was 6 months old - telling the capacity crowd of 1,503 it was the cat's stage debut - a little white tiger lie.
Montecore was told to lie down, but balked and grabbed Horn's arm in his mouth. Horn struck Montecore with his microphone, trying to get him to loosen his grip. Montecore then grabbed Horn by his throat, dragging him backstage where handlers subdued the tiger by spraying him with a fire extinguisher.
Horn remains in critical but stable condition. One of the doctors who treated Roy Horn after he was attacked last week by a tiger said Tuesday the magician is improving and communicating, but is still in critical condition.
Neurosurgeon Derek Duke said Horn's injuries were severe, and is not sure if he will fully recover.
Horn prided himself in knowing his animals and his animals knowing him. In more than 40 years of close encounters with some of the world's most exotic animals, Horn was never injured by any of the creatures, Horn said in a 2000 interview for the book "Siegfried & Roy's Gift for the Ages."
"Siegfried and I have spent every waking moment with our animals," Horn said. "We watch and observe. We talk to them, take walks with them, swim with them, meditate with them. Day by day, we learn about each other. But you must have patience and respect for Mother Nature. Because when an animal gives you its trust, you feel like you have been given the most beautiful gift in the world."
Horn said whatever situation he's put in with his animals, "I always try to think as they think. We can always solve our arguments in an understanding way because I respect them and they respect me."
Only once was that philosophy tested, he said in the 2000 interview.
He was playing hide and seek, as he often did, with a Siberian tiger named Sahra.
"After rolling around in the grass together, she suddenly laid on top of me and pinned me down," Horn recalled. "Our eyes met and I realized she was no longer playing - she was about to bite me. Trusting my instincts, I raised my head and bit her nose as hard as I could."
"Totally perplexed, she jumped up and pretended it never happened," said Horn. "I immediately made our friendship sound - ff-fuff, ff-fuff. She never attempted to bite me again."
The bonds with special animals begin at an early age. When a white lion or white tiger is pregnant she is cared for at special birthing facilities at Siegfried & Roy's Secret Garden, an animal habitat at the Mirage.
"I think this is incredible when you consider an animal like this can kill their own mate over young ones, and to think that she accepts Roy to be a part of the experience is a miracle," Fischbacher said.
Horn's love of animals dates back to post-war Germany, when his father returned home from the German military with an animal that was half dog, half wolf. Horn and the dog, Hexe, became inseparable, spending their days wandering in the nearby woods.
"If it wasn't for Hexe, I wouldn't be sitting here today," Horn said in the interview. One day Horn was sucked into a swamp area and began sinking. Hexe raced to a nearby farmhouse and brought help, Horn recalled.
Horn left home at an early age to become a bellboy on the cruise ship, where he met Fischbacher, a young magician who was one of the ship's entertainers.
The two first played Las Vegas in 1966, then returned as a featured act in 1974. They signed an unprecedented $57.5 million contract to play the Mirage in a theater bearing their name beginning in 1990. In 2001, after performing some 5,000 shows before more than 7 million people at the Mirage, they signed a lifetime contract with the resort.
The day after the attack, the show was shut down indefinitely.
Robert Macy has covered Siegfried & Roy for 22 years. He was Las Vegas correspondent for The Associated Press from 1981 until his retirement in 2000, after which he and his wife Melinda wrote a book, "Siegfried & Roy's Gift for the Ages," which focused on Roy Horn's passion for saving rare white tigers and white lions from extinction.
By Robert Macy