The WWE said Warrior, who legally changed his name from James Hellwig to his wrestling moniker, died Tuesday. Scottsdale, Ariz., police spokesman Sgt. Mark Clark said he collapsed while walking with his wife to their car at a hotel and was pronounced dead at a hospital.
There were no signs of foul play, Clark said. The Maricopa County Medical Examiner's Office will conduct an autopsy Thursday, county spokeswoman Cari Gerchick said.
WWE Chairman Vince McMahon tweeted: "We are all so sad the Ultimate Warrior has passed away. Our heart is with his wife Dana and his two daughters."
"Vince said to him a couple of days ago, 'I've always loved you. Sometimes, I didn't like you, but I always loved you,'" Levesque said.
Warrior and McMahon posed for a picture Monday night that Stephanie McMahon tweeted, "Never say never."
Waltman attended the Hall of Fame ceremony and saw Warrior before he went on the stage to make his speech.
"I got a sense he wasn't well," Waltman said. "It was sad to me. He was kind of hunched over. He used to have such great posture. You just had this sense that he wasn't well. But he was in great spirits. He came up to (other wrestlers) and gave them hugs."
The Ultimate Warrior had a falling out with the WWE over various issues, including money, and did not appear on its TV shows after July 8, 1996, until last weekend.
Levesque said he spent 18 months getting to know Warrior and both sides put hard feeling aside to bring him back into the WWE fold. He said Warrior was like a "kid reborn" to headline Saturday night's Hall of Fame class. Warrior had signed a deal to work as a WWE ambassador.
"It was time to move on and get past all of it," Levesque said. "In some ways, when you've been in this business and in the WWE, you're all brothers. Can we get back to being brothers?"
The WWE Network was set to air highlights from the Hall of Fame and WrestleMania 6 on Wednesday night, and a dedicated tribute show will run next week.
Warrior was the only Hall of Famer feted with his own moment on Monday. His final words to the crowd are ones wrestling's fanatics will surely take to heart.
"The spirit of The Ultimate Warrior will run forever," he said.