The experts look at the hands.

Like rural folks dropped in the middle of a big city, awed by the towering skyscrapers, novices are distracted by the sounds and graphics, the artistry of video games. At Tilt, a cavernous arcade in the Laguna Hills Mall, the masters of the games are like The Who's Tommy, deaf to the bells and whistles. They look at the wrists."You look for secrets," says Chywan Marrero, 17. "Everybody knows more than I do."

But the Mission Viejo resident isn't that convincing as the ignorant player. He expertly moves the joystick and five action buttons of Mortal Kombat II, the most popular arcade machine in the United States: a fighting game constructed from videotapes of actual martial artists in action.

The graphics are incredibly realistic, with full-background scenery, intricate combat moves and a perfect computer synthesis of a human voice.

"Fight!" the machine yells. Across the country, kids are listening.

Referring to his $50-a-week habit of late last year - the game premiered in November at Tilt - Marrero says, "I wish I hadn't spent that much." But watching his opponents' wrists and picking up cheat sheets at school or on computer information networks taught him many secret moves.

Now he can play the game for hours without being defeated by competitors or the computer and ultimately makes 50 cents last a long time. These days, he spends about $20 a week on games.

"I can rip people's intestines out and all that," he added, his face reflecting the pale glow of the screen.

Kombat II is at the forefront of video games, the latest incarnation in 22 years of entertainment-technology refinement. Since the first video game, Pong, was created in 1972, the business has exploded faster than Missile Command and mushroomed more than Super Mario.

In 1992, video games brought in $5.3 billion in the United States, according to industry figures. And there is every indication that they will continue to grow.

"There's always kids playing that game," Nia Bousary, an employee at Bally's Aladdin's Castle in Buena Park, says of Kombat II. "What do kids do on weekends but hang out in malls?"

And what do kids do after school but hang out in malls? Any psychologist who named the latchkey generation "lost youth" apparently never looked into local retail.

On any weekday afternoon, Laguna Hills Mall has packs of roaming kids and a mostly male crowd of about 40 in Tilt. Bousary, 21, says Aladdin's Castle makes $150-$200 a day on Kombat II alone, a game that arcades can buy from a dealer for only $4,000.

Bally's Midway, the company that makes Kombat II, has made an estimated $100 million since introducing the game in October, according to Video Games and Computer Entertainment magazine. And Kombat II is only one game in hundreds marketed by companies such as C.A. Robinsons, an amusement dealer in Los Angeles.

Ira Bettelman, vice president of C.A. Robinsons, says he has sold about 200 Kombat II games and more than a few competitive driving games, which retail for more than $10,000.

All this profit ultimately grows from the 50 cents (few new games cost a quarter anymore) that children drop into slots every day in arcades across Orange County. So popular are arcades that Jonathan Galarza of Laguna Hills spends $2 a day, most of his allowance, on video games.

"Just to figure out a new fatality and stuff," the 10-year-old says. "I play a couple times a day."

Galarza is just as good as any of his teenage competitors, despite coming up only to most of their shoulders. Video games are the great equalizers, where the physically small are powerful, the nerdy garner respect. A child beaten up on the playground easily can turn around and pound everybody else, in the alter ego of a martial-arts expert.

This role playing is enhanced by games that get better and better at putting the players on the screen. The new Virtua game series from Sega has three-dimensional graphics with impressive depth; Virtua Racing raises the ante with a player's seat that moves with the screen.

In the late 1970s, video games were the disobedient students confined to corners in smoky pool halls, greasy pizza parlors and flashing pinball arcades. Today, they have taken over, elbowing pinball machines and pool tables into the back corners, transforming pizza parlors such as Chuck E. Cheese into slaves to the video.

At Chuck E. Cheese in El Toro, pizza takes a back seat to games such as X-Men, which allows players to be their favorite member of the superhero clan on a wide-screen, high-resolution machine. Francis Tan of Mission Viejo sums up the trend simply while going over a cheat sheet.