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DAVID KATZ HAD a blank, chilling countenance, a vacant stare his own father once described in court as "looking right through you." To his fellow competitors, it seemed out of place in Jacksonville, Florida, on the weekend of Aug. 25-26, during the first Madden NFL 19 esports tournament of the season. The latest version of the iconic game had been out only a few weeks when the small, tight-knit group of elite pro Madden players -- a "brotherhood," they called themselves -- reunited at the Jacksonville Landing open-air mall downtown. Inside a small, noisy game room in the back of Chicago Pizza and Sports Grille, they laughed, drank, talked trash and battled for $5,000 and a coveted spot at the Madden Classic in Las Vegas this fall. But when a fellow gamer tried to engage Katz in small talk on the first day, Saturday, by asking what upcoming Madden events he was looking forward to, Katz cut him off. "Don't worry about it," he snapped, turning away.

During the past few years, playing as "Bread," Katz, 24, had started to make a name for himself in Madden circles, both for his gameplay and his odd behavior. After driving 11 hours from Baltimore with little more than the clothes on his back and -- unbeknownst to his competitors -- a small cache of handguns, Katz appeared at the tournament wearing mirrored sunglasses, a purple Ravens backpack and a blue and gray plaid shirt. He would wear the same thing on the tourney's second day.

Madden might be an iconic brand, with 130 million games sold, but the setting in Jacksonville summed up its minor league status in the otherwise burgeoning billion-dollar esports industry. At a recent Dota 2 competition, for example, the winning team pocketed more than $11 million in a single week. In Jacksonville, at the pizza joint hosting the tournament, there weren't even enough gamer chairs to go around.

On the opening day of competition, Katz won twice during pool play and lost once, to Dennis "Evil Ken" Alston, a Madden pro from New Jersey. Afterward, when Alston offered his hand, Katz didn't reciprocate, he says. He just glowered at Alston with that cold stare.

The next day, playing in the single-elimination tournament under the name "SatiricBulb," Katz tied up his game in the second half and then recovered the ball after a surprise onside kick. His opponent, Reginald "Boogz" Brown, calmly paused the game, expecting the play to be overturned by a tournament official because he thought pro players had to be trailing in the second half to use an onside kick. The rule, though, had recently been changed. Katz retained possession. "Good stuff," Brown responded with a laid-back nod, acknowledging Katz for exploiting the rule change. Katz said nothing.

He was unable to do anything with the extra opportunity. Eventually, Brown punched in the winning touchdown to advance, and the game ended without incident. But whether it had happened days, weeks or months before, or in that very moment, something inside Katz snapped.

"It wasn't much longer than five to 10 minutes," Brown says, "before the first shots were fired."

Elijah Clayton, one of the two victims, had been saving his Madden winnings to pay for college. Courtesy Jacksonville Jaguars

IN THE MIDDLE of the night, with his Xbox controllers locked up in his mother's bedroom in Columbia, Maryland, an adolescent David Katz squeezed his hand into a fist, gathered his rage and punched a hole through the bedroom door.

Richard and Elizabeth Katz divorced in 2005, when David was 12 and his brother, Brandon, was 15. Richard and Elizabeth's legal battle, which went on for a decade, produced hundreds of pages of court records and medical documents that offer a window into David's life leading up to Jacksonville, especially the way his mental health care became an issue between his parents. Richard and Elizabeth, who are cooperating with the FBI, could not be reached for comment.

When divorce proceedings began, a therapist described David in court documents as possibly having a "psychiatric crisis" due to worsening depression that interfered with his eating, sleeping and willingness to get out of bed. He began taking antidepressant medication as well as Risperdal, an antipsychotic drug used to treat schizophrenia and bipolar disorder. Richard challenged his son's diagnosis and in court accused Elizabeth, a toxicologist at the U.S. Food and Drug Administration, of having "an obsession with using mental health professionals and in particular psychiatric drugs to perform the work that parents should naturally do." He also testified that a psychiatrist recommended David stop taking the drugs, and he entered into evidence an FDA study on the increased suicidal thoughts and actions of people 18 and younger who take certain antidepressants.

In a 98-item findings of fact from 2006, the court summed up the situation: "There are serious issues regarding the children upon which the parties have fundamental differences of opinion, not the least of which are how to handle the children's mental health needs and educational needs. ... Both parents are intelligent, well-educated people. It is unfortunate for the children that both parents are so focused on the litigation that the children's needs seem to be taking a back seat."

In August 2007 and again in December, David, then 13, spent approximately two weeks in psychiatric care facilities in Towson and Rockville, Maryland, because he was depressed and skipping school, according to an affidavit from Richard. In January 2008, he was taken involuntarily to a therapeutic wilderness school for teens in Utah. Court records say that when depressed or agitated, he would suffer crying jags, collapse into the fetal position, lock himself in his mom's car or pound his hands against his head. In a 911 transcript from 2009, Elizabeth tells the operator: "He's sitting here, wrestling me with the cable cord to the TV. I've had enough with this child. He has been abusive for over two years."

The next year, David was failing most of his classes at Hammond High School in Columbia and staying up until 4 a.m. during the week to play video games. Elizabeth and David battled constantly over his Xbox, to the point where an attorney said in the court records, "This is not Xbox court." His mom told a Howard County judge: "His hair would very often go unwashed for days. When I took his gaming equipment controllers away so he couldn't play at 3 or 4 in the morning, I'd get up and find that he was just walking around the house in circles, just walking around in circles."

In a letter dated Dec. 22, 2009, written in pencil in clear handwriting on loose-leaf paper, David asked the court to let him live with his father. "Dear Judge," it begins, "Today is my birthday and I'm turning 16 years old. I live with my mom and have been wanting to live with my dad. My mom is pretty crazy. She's called the police on me about 20 times for pretty much nothing like coming home a little late or something. She also gets drunk and starts yelling at me and poking me and doesn't leave me alone. She has hit me before and always takes my stuff because she feels like it. ... I hate her more than anything in the world. ... Sincerely, David Katz."

A lawyer appointed to represent the children's interests had previously recommended that Elizabeth be granted sole custody of David. The court appeared unwilling to override that recommendation, because less than four months later, David wrote another letter asking again to live with his dad.

Still, David managed to graduate from Hammond High in 2011 and registered at the University of Maryland in 2014, majoring in environmental science and technology. He did not graduate and was no longer enrolled by 2018. At some point as a young man, David moved to his father's home in Baltimore's Inner Harbor, where he was living at the time he drove down to Jacksonville. Richard, a NASA engineer, once told the court he thought David was "physically strong and mentally does not need drugs." Father and son, he said, shared a love of baseball and would play catch, spend time at a nearby batting cage and attend Bowie Baysox games together.

Through all of his struggles, Katz continued to play video games, and by 2017, he'd put together a run of successful Madden tournaments. In February 2017, he was responsible for what EA Sports described at the time as the "most exciting moment in all the 2017 NFL Club Series Championships." Playing in the finals of the Buffalo division, with time running out and the score tied at 20, the seventh-seeded Katz threw a Hail Mary to upset the top-seeded player, Carlos "Los" Yancy. He won $3,500 and a trip to Los Angeles for the Madden Club Series Championship. In a congratulatory tweet sent out by the Bills, Katz appears gaunt and expressionless. A month later at the championship, a Madden announcer said, on-air, that getting Katz to open up and talk about anything at all was like pulling teeth.

The game he excelled at happened to have one of the most social communities in esports. All the important tournaments are in person: big, loud, crowded spectacles with face-to-face matches. The sanctuary and respect Madden offers its top players is built on its strong sense of community, and many say that to truly be accepted, a player has to socialize. "We rag on each other and we argue all the time, but at the end of the day I love all those guys," says Madden competitor Tony "V-tech" Montagnino, 34. "When I go to tournaments I'm very outgoing. It's always, 'Hey, how's your family? How are your kids? Let's go to the bar after and have a drink.'"

By the time the 2018 season opened in Jacksonville, Katz had added to his savant-like grasp of Madden minutiae, allowing him a strategic advantage on moves like second-half onside kicks. But his fellow competitors describe his behavior inside Chicago Pizza as detached. (Richard Katz and the FBI have not said what, if any, medication David was taking that weekend.) Jordan "Kandoouu" Kandah, one of the players Katz beat on the first day, said that Katz had seemed "a little on edge" and "didn't say anything but a few words." Whatever Katz was thinking or feeling, it was locked away.

A Madden Classic champion, Taylor Robertson was a 27-year-old father and husband from West Virginia. Courtesy Titans

KATZ RE-ENTERED CHICAGO Pizza on Sunday afternoon minutes after his loss through a single, worn metal-framed glass door with a 10-foot Mario Bros. portrait on one side and a poster on the other exclaiming: "There are shortcuts to happiness and dancing is one of them." It was just before 1:30 p.m. He carried .45-caliber and 9 mm handguns that police say he purchased legally in Maryland less than a month earlier. (Maryland prohibits people with a history of mental illness from purchasing or possessing firearms, but Katz would have had to self-report those issues.) He had extra ammunition and an aftermarket laser sight.

Around 150 people were in the building, many of them packed into the GLHF (Good Luck Have Fun) Game Bar near the restrooms in the back corner of the pizza joint. Police say Katz walked past the hostess stand and through the restaurant into the game room, where it was so crowded spectators had to turn sideways to move through, and there was little to no security.

Katz pointed the red laser sight of his 9 mm at the chest of Elijah "Trueboy" Clayton, playing in the coveted feature-game console next to a livestream commentator's booth. Clayton, popular and brash, was one of the most talented players. Wearing a burgundy Adidas hooded sweatshirt and white headphones, a smiling Clayton glanced to his left before refocusing on his game and the Falcons' kickoff. He didn't notice the red laser sight dart erratically across his chest, then disappear.

A split second later, it reappeared. This time it was a steady, solid dot hovering over Clayton's heart. Anyone watching the livestream of the tournament could see it. Katz opened fire, hitting Clayton at least twice in the chest. Clayton slumped in his gamer chair, his head contorted to the side. He died moments later.

The room became a dizzying pit of terror, panic, smoke and screaming. The livestream's video feed cut out. Two huge windowpanes on the back wall cracked into a thousand pieces. On the livestream audio that remained, the screams, moans and sound of glass, furniture and bodies shattering mixed with the furious and relentless pop-pop-pop of the gun. For those in the room, it seemed like it would never end. In disbelief, some thought they were hearing balloons bursting; others thought it was a cap gun.

Tony Montagnino hoped it was fireworks. Montagnino, seated with his back to Katz, felt something white-hot pierce his lower back. The force of the bullet spun him around to face the shooter. He recognized Katz's shirt, the one he was wearing all weekend. Katz's face, however, was largely blocked by bursts of smoke from the barrel of the 9 mm as Katz continued to mumble to himself while firing into the crowd of his peers. "Oh, f---, what'd he shoot me with?" Montagnino yelled before diving to his left for cover, along with several other players, behind the overturned plastic announcer's table.

Montagnino collected himself enough to realize: If he comes over here to clear out the room, I'm screwed. None of his choices felt right, but he willed himself to his feet and lunged for the back exit door toward the sunlight and the St. Johns River beyond, careful not to slip on the beige tile floor becoming slick with blood. The exit was crowded, with at least four people clawing and trampling one another to escape.

Timothy "oLARRY" Anselimo, 25, had been standing over Montagnino's right shoulder, near the back door, when Katz opened fire. One bullet struck him in the chest. Another entered near his wrist and tore through his hand. Trying to get outside -- "my only chance," Anselimo says -- he was hit yet again in the left hip. He fought his way through the door and stumbled toward the shelter of another restaurant. His middle finger hung off his palm, leaking a trail of blood.

Montagnino tried to follow Anselimo out, but people seemed to be stepping over and around something just beyond the exit, on the redbrick patio outside. Once Montagnino reached this point, he looked down and froze in his tracks. Taylor Robertson was flat on his back, mouth agape, staring blankly at the sky. Montagnino felt his knees buckle. "Not Taylor," he thought, the 27-year-old dad from West Virginia known as SpotMePlzzz. "Not the most soft-spoken and humble guy in Madden. It couldn't be."

It was just as chaotic on the patio -- people fleeing frantically in all directions -- and Montagnino thought Katz might actually have come outside. Montagnino shuffled back inside the smoke-filled game room. He pounded on the bathroom door. Two older men cracked the door a sliver and stared at him apologetically. No room. The door shut in his face. "At that moment, I gave up," Montagnino says. "I gave up and laid down on the ground and I thought, 'I'm either going to die here or someone's going to come help me.'"

Montagnino surrendered himself to the cold, wet tile floor. The sulfurous smell of gunpowder smoke stung his throat and nostrils. The bullets had stopped, and the room had fallen so deathly quiet he could hear Travis Scott's "Stargazing" playing on a pair of headphones discarded in the melee. Scanning the floor, he spotted a custom-painted Xbox controller about 10 feet past the headphones. The green, cackling face of the Joker stared at him, along with the words "Why so serious?"

Blinking back his dimming consciousness, Montagnino thought of his wife, Staci, and their two little girls back in Texas. A competitor nearby let out a scream full of anger and agony: "I told y'all that guy was coming back."

Several first responders, conducting a training exercise across the street, arrived at 1:36 p.m. and, without protective gear, rushed into the restaurant. Katz had already backed into the archway leading to the restaurant. Two were dead; 11 were wounded. He put the gun in his mouth and pulled the trigger.

Inside the game room, no one knew this yet.

"Where'd he go?" they screamed, over and over. "Where'd he go?"

Even in this congratulatory tweet from the Bills after a career-best performance, Katz (right) appeared expressionless. Twitter

AT DUSK, THREE days after the shooting, there were tiny wooden cross necklaces tied to the front door of Chicago Pizza and biohazard orange tape tied to the back. At 7 p.m., the string lights that decorate the patio behind the game room, some of them tiny R2D2s, flickered back to life automatically. At the restaurant next door, a family with two giggling toddlers enjoyed a taco dinner, their table only feet from dried bloodstains.

The first lawsuit against EA Sports and Chicago Pizza for negligence had already been filed by a survivor who was shot twice. The sheriff told the media that as bad as the shooting was, it could have been much worse. The Jacksonville fire marshal posted an orange cease-and-desist notice on the front door of the restaurant declaring that the game room had never been properly permitted, in part due to the obstructed exit. These small Madden "locals" had been one of the last places in sports, virtual or otherwise, where talented, anonymous players could still go straight from their den to the big time in one weekend. Already, the charm of these events felt like ancient history.

Anselimo, a salaried member of the Milwaukee Bucks gaming team, was still at University Hospital in Jacksonville, scheduled for two surgeries to repair his hand. Too dangerous to extract, the bullet in his chest remained. From his hospital bed, he tweeted about the hero who saved his life: the Hooters cook who got him to safety, triaged his hand and bear-hugged him to keep pressure on the wounds until his own shirt was so soaked in Anselimo's blood that the police took it as evidence.

Shay "Young Kiv" Kivlen, 21, who had been close friends with both Clayton and Robertson, wondered in horror if he had narrowly escaped. He had gone back to his hotel just before the shooting to take a nap. Katz had been heard asking the EA rep where Kivlen had gone and when he might return. The reigning Madden NFL 18 Bowl champ had turned on the tournament's Twitch stream and heard, along with everyone else who had tuned in, the gunshots and screams.

Montagnino was using Madden, and a twisted sense of humor, to recover as best he could. (Online trolls accused him of being a crisis actor, which didn't help matters.) A bartender in Texas, he asked paramedics to stop when he was wheeled out of the restaurant on a stretcher. "Told them I still needed to close my tab," he says. "Physically, getting shot sucks and it hurts, but the mental aspect of it is 100 times worse. Was I a coward for looking out for myself? I still hear the screams, the noises. I smell the smoke from the gun. Everything about it runs through my head as soon as I lay down."

In the aftermath of the rampage, one detail in particular still puzzled many of the survivors. At first the idea that Katz was mumbling incoherently during the shooting was somehow reassuring. It suggested to them that he was unhinged, a crazed lunatic. But the reality of what may have been behind that cold, distant stare felt far more chilling. Two uninjured witnesses who were within feet of Katz during the shooting said he wasn't babbling at all. They said he was counting to himself, almost under his breath, methodically keeping track of how many shots were fired.

The prevailing theory is that Katz wanted to be certain he had saved one final bullet, for himself.

Additional reporting by Kevin Van Valkenburg