The center hosts a gaming tournament or league match almost every night and weekend. One Saturday morning this fall, I found it full of young men and teen boys wearing sweat shirts and blue jeans and carrying binders, beat-up briefcases, science-fiction novels and stacks upon stacks of gaudy playing cards.

Two hundred players - 190 of them male - filled long tables. They were preparing to play Magic: the Gathering, a complicated card game created by Wizards of the Coast that features stunning fantasy artwork, warfare involving creatures and sorcerers, and an ever-growing array of cards.

Two players act as dueling wizards, sending forth creatures and warriors and casting spells. Each side starts with 20 points of "life" and they play to the death. Magic combines the strategy of bridge or poker with the fantasy world of Dungeons & Dragons, the classic role-playing game.

Players entered this tournament mainly to receive a two-week head-start collecting the latest cards (more than 4,000 have been released since the game was first published in 1993) that Wizards would be shipping to retailers. Among them were the black "Agonizing Demise" card featuring a field of fallen soldiers. "Smoldering Tar" shows a sorceress cooking up a steaming enchantment. "Razorfoot Griffin" contains the italic quote, "Do griffins fight to defend their homes or purely for sport?"

That means gamers, like a teenager with multiple pony tails whom I watched chug pack upon pack of powdered sugar as he played, will bolster their collections through trading and by buying new cards from minipacks and 75-card expansion sets released every four months.

Magic not only created a whole new game genre - the trading-card game - but transformed Wizards from a scrambling little enterprise in founder Peter Adkison's basement to a multimillion-dollar company. It made Adkison and fellow gamers and investors who helped him start the company rich.

Although the company has little mass-market name recognition, Wizards is as dominant in its world as Microsoft and Starbucks are in theirs. The success of Magic gave Wizards the clout to buy the company that owned Dungeons & Dragons, a game it is working hard to resurrect. Last year, Wizards applied the Magic formula to the Pokemon Trading Card Game for children and struck gold.

It now is trying to tap into the next obsessives - sports fans - by releasing a Major League Baseball game last April and an NFL game next year.

I can handle RBIs and home runs, but having learned the basics of Magic just the day before, I could make little sense of the games I watched or the excitement over the cards. But then, I'm not the demographic. I'm too old and too busy. I'm not analytical enough to appreciate the byzantine strategies of Magic. I'm not compulsive enough to keep buying the waves of new cards or trading them as I did my baseball cards as a kid.

Much of Wizards' work is what the company calls "the metagame" - tournaments, worldwide rankings, book publishing, magazines, elaborate artwork, figurines and constant "customer training." Magic even has a professional tour, in which a twentysomething has won $190,000 by playing cards.

Research and development is the backbone of both the game and the metagame. Mark Rosewater, who helped design the latest batch of Magic cards, watched the same basement tournament I did to see what cards created a buzz among players.

Inside is a different matter. Walking the maze of narrow halls, I passed Nerf weapons, hockey sticks and guitars, guys playing video games, garish posters, hanging fish balloons, maps of fantasy lands, cubicles and desks crammed with figurines, fluffy toys, 20-sided dice the size of basketballs and, of course, boxes upon boxes of product.

At lunchtime, young men, often dressed in T-shirts and baseball caps like the game-center crowd, play Magic or other company card games. There's a ping-pong table, a row of video-game stations and a tavern-style basketball hoop. Twice a year, work shuts down so employees can just play the games.

I sat down in a conference room just after 6 one Wednesday night to watch six employees play their weekly Dungeons & Dragons game. In D & D, participants assume roles and work together to navigate through adventures. A cult rage in the '70s, it became passe over the years. Wizards has put a lot of effort into revamping the game since buying the failing company that invented it.

Amid incessant needling, each player sitting around the table acted a role: a barbarian, a thief, a spell-casting cleric, a perennially frightened gnome and so on. A young guy with bleached hair and two lip rings played Olga, a woman with a pet flying griffin.

Christopher Perkins, editor in chief of Wizards periodicals, kept the narrative humming as the dungeon master (part story-teller, part referee).

The game I watched had been going on weekly for two years. I witnessed the group dealing with a ghostly possession, searching for a kidnapped comrade and confronting various enemies. Each situation was influenced by the characters' personalities, decisions and capabilities, then settled by the roll of 20-sided dice.

About the time the adventurers were fending off monsters that looked like four-armed flame-throwing gorillas, I noticed the groan of a janitor's vacuum cleaner in the hallway and realized I had been sitting there for more than three hours.

There was another D & D game on the other side of the building and a Magic play-test session downstairs that night.

The playhouse atmosphere extends to CEO Adkison's office. When I met him there, almost half of it, and all of his conference table, was taken up by a square plastic field and its miniature warriors. An erase board listed characters such as "gnomes" and "the undead." A wizard mannequin sat in one corner. Original D & D artwork hung on a wall. A $700 surfboard dangled from the ceiling.

Adkison, 39, is friendly and casual, with a goatee and bleached hair. He laughs easily and tries hard not to sound like the boss. He cringed a bit each time he uttered management-speak, using finger motions to signal quotation marks when he said, "the team."

Last year, Hasbro, the huge company known for G.I. Joe, Tonka Toys and Monopoly, bought Wizards of the Coast for $325 million. Gamers worry that Wizards, now a division of Hasbro, will be absorbed by "the suits." So far, though, the influence seems negligible. Adkison still runs Wizards and says as long as it is profitable, things won't change much.

"It was Christmas 1978 and I went to the store with $30 burning a hole in my pocket," he said. "I was looking for another war game and right there was a blue box set of D & D. For a long time, fantasy to me was the Wizard of Oz, but I had just read J.R.R. Tolkien and there was a dragon on the cover of the game so I said, why not?"

"My first reaction was, `Wow, a game with no rules?' Basically, I spent so much time doing it as the years passed that I decided I should try to do a side business out of it."

In 1990, while working as a Boeing systems analyst, Adkison started Wizards of the Coast to produce similar role-playing games, which use manuals, dice and imagination but little other equipment. The next year, while discussing games in an Internet forum, he learned of Richard Garfield, a mathematics Ph.D. candidate at the University of Pennsylvania who had invented a board game and was looking for someone to publish it.

Adkison felt he couldn't make money on the board game, called RoboRally, or any board game, for that matter. They were too expensive for a small company to tackle. But he knew Garfield was smart so he set up a meeting.

Adkison told Garfield he was looking for something compact and fast that people could play at gaming and science-fiction conventions. He said cards with cool artwork might be good.

About a month later, Garfield came to Seattle for a convention and in the parking lot across from KeyArena described his idea for a trading-card game. It was a new concept, but Adkison got it immediately. He began yelling and dancing among the parked cars.

Garfield, a placid, thoughtful sort, remembers cautioning Adkison: "Now remember, we don't have a game yet. It's just an idea."

Nevertheless, Adkison plowed ahead, using his Boeing salary and small investments from friends to fund operations while Garfield returned to Pennsylvania and spent more than a year developing and testing the game.

Wizards' first paid employee was Lisa Stevens, a D & D fanatic who had helped start another role-playing game company called White Wolf. Stevens, who now is brand manager for Wizards' new "Star Wars" game, had valuable marketing experience and distribution contacts.

Adkison set up the business in the basement of his Kent home and gave Stevens extra shares for use of her computer - an arrangement she now calls "a very, very good rental deal."

The company's few employees had to work second jobs while waiting for Magic. Stevens did freelance work; another employee moonlighted as a bouncer in a strip club. Artists, many of them students at Cornish College of the Arts , created playing-card images for a few hundred dollars and company stock that they had to suspect would be worthless.

"When I first came up with the concept of Magic, I didn't know if such a game would be possible - I mean possible and good," Garfield told me. "It is easy to imagine a game in which you construct your own deck and it winds up being stupid because everyone just plays with the aces."

Finally, in 1993, Garfield became satisfied that the card strengths were balanced enough so that there was no ace that, by itself, would trump the others. The key to the game was that players would amass cards at their own rates and build their own decks.

"A lot of things about the concept turned out to be gold from an economic and business standpoint, but what excited me was not that someone would buy a jillion cards," Garfield said. "What I liked was you could be your own game designer. You could play the cards you wanted to."

When Magic rolled out in August 1993, its success was stoked by an Internet buzz and Adkison's barnstorming demonstration tour of West Coast hobby shops. When Wizards took the game to GenCon, a huge gaming fan-fest that it now runs, Magic was the rage. It sold 10 million cards in its first six weeks.

The company went from start-up hell to high-growth hell. Eventually, Adkison enrolled in a business program so he could understand the MBAs he had to hire.

In 1997, Wizards bought TSR, the makers of D & D. With it came a fantasy-adventure book publishing wing. Now, Wizards is the top producer of not only trading card games but also role-playing games. It opened the University District game center in 1997 and bought a chain of retail stores last year.

When Wizards licensed the rights to produce a Pokemon trading card game, based on the popular Japanese animation product, the company tapped a mass market for the first time and found an eager suitor in Hasbro. The stock Adkison had been passing out was now worth a lot of money. About 30 early employees and investors became millionaires.

In 1992, Wizards had sales of about $100,000. Last year, sales approached $500 million.

IZARDS of the Coast has about 1,900 employees worldwide, about 900 at the Renton complex. None are more important or given more freedom than the research and development teams.

Garfield is a vice president with no management responsibilities, a free-floating tinkerer. He sits in a cubicle among other designers because he turned his office into a game room packed with classic titles such as Risk and Uno and obscure ones such as Gang of Four.

Garfield has designed 10 games, from RoboRally to a party game called "What Were You Thinking?"

I had a college dorm room flashback when I walked into the Magic R & D area. Young men sat around tables cluttered with dice, papers and change jars, play-testing the Magic cards that will be released next fall. They were looking for "broken" cards - those that would be too powerful in play. Such a card occasionally gets by them, only to be exposed on one of several Web sites devoted to analyzing every Magic card. Broken cards are banned from tournament play, but they work like aces in casual play.

Like the players they target, most of the R & D crew are young men and hard-core gamers. Usually they have backgrounds in math or science. Randy Buehler, a former pro player, joined the company a year ago. He's on the development team, which acts as the editors of what the designers dreamed up. At 29, Buehler has degrees in both physics and philosophy and is a portly, competitive guy who was far better at "College Bowl" than basketball.

He won $55,000 in his two years on the pro Magic tournament before joining Wizards last fall. As a player, he was known for decks he devised - especially "Buehler Blue"." In those days, he practiced an average of 40 hours a week and spent perhaps $1,000 a year on cards.

"Magic basically took over my life," he said.

Buehler is working on the next expansion set for Magic. He's banned from pro tournaments but serves as color commentator for the Magic world championship, which ESPN2 broadcasts. The top player in the world, Jon Finkel, has earned $190,000 so far.

R & D folks also are hard-core gamers, which makes Garfield's office, nicknamed "the danger room," a library of sorts. Designers and developers tinker and study all kinds of games.

"We have our own version of hearts at lunchtime that we call "turbo-hearts," Buehler said. "We change some rules, like doubling the point value for the Queen of Spades if you show everyone you're holding it before the round starts. Things like that. We have kept the points in a database going years back."

Bill Rose, who met Garfield while attending Penn, is the vice president who oversees Magic, coordinating R & D work, the naming team, the artists who put faces on the cards and authors who write an accompanying book providing a back story for the game.

Rose, already working on the 2002 edition, said artwork and names of the cards must be designed to quickly clue players about how to use them. Card colors have a consistent logic - red is chaotic, for example, and blue controlling but passive.

Role-playing designers work on the other side of the R & D floor. They focus less on numbers and probabilities, more on selling a fantasy-game experience. They write and edit manuals and constantly play-test.

A priority is applying the Magic treatment to D & D. Wizards has already overhauled the game, ridding it of the bikini-clad babe-warriors employed by the former manufacturer and simplifying the rules. Its new edition of the player's handbook, describing rules and character traits, rose to near the top of the New York Times best-seller list early this year.

While Garfield foresaw the playing possibilities of a trading-card game, he didn't fathom the scope of its market. He envisioned having to produce new, stand-alone sets each year, not the one evolving, never-ending card set that Magic has become.

He didn't like the idea of having a back story. But Wizards' book publishing section churns out about 50 adventure novels a year that outsell the games. Wizards also publishes two magazines that report on strategies and promote its products.

There are employees who field phone calls from players stumped on the rules. Everyone in the company is keenly aware that people don't generally read instructions to anything, let alone multi-layered games, so it has a big Web presence and sends employees to stores and tournaments to play (called gunslinging) and demonstrate.

A few miles from the main office is a small plant that manufacturers pewter miniatures of sword-wielding warriors, dragons and other characters. Wizards is deciding how aggressively to go after the miniatures (what I called `army men' in my youth) market.

There is a department devoted to organizing tournaments and leagues all over the world. Skaff Elias, a vice president and game designer, gets much of the credit for establishing the tournament circuit.

"In my family, games were just games and that meant not worth spending your time on," Elias said. "I didn't believe that was true. I wanted to make it into a mind sport. Chess is an example, the way a champion chess player can be a national hero in Europe."

A pro tournament legitimizes the game for the casual players, Wizards believes, just as the National Basketball Association affects people who play pickup games. The company studied how much money people were willing to pay to support their golf and tennis games and determined that Magic players will spend less than golfers but more than tennis players.

Then there is the fantasy artwork, important to collectors as well as to the aura of the games. There are six artists and a sculptor on staff and many more freelancers. Together, they produce about 20,000 pieces of art a year.

When I met John Schindehette, vice president of creative services, he was zipping through a large box of applications from artists. He needed only a once-over to decide which ones to flip into the rejection pile on the floor and which ones showed promise. He looked for the form and sense of movement.

"You wouldn't believe how many puppies and flowers we get," he said. "We do monsters and half-orcs, not puppies and flowers."

AGIC BEGAT the Pokemon trading card game (yet another edition rolls out next month) and the worldwide success of Pokemon emboldened Wizards to strike out into the mainstream. It has games based on Looney Tunes, "Star Wars," professional wrestling and the X-Men comic book and movie. It is preparing a Harry Potter product.

It wasn't until I tackled the relatively new and comfortably simple Major League Baseball card game that I could appreciate the insidious lure of the trading-card concept. In the baseball game, cards represent Major League players with strengths reflecting their real-life performances. I grabbed a starter set that included 12 players from each league and added four, 9-card booster packs that also included strategy cards.

That total cost was about $20 for what turned out to be an American League team with five catchers and Gary DiSarcina of the Anaheim Angels as my lone shortstop. Weak-hitting Gary DiSarcina? No way.

So I ripped open another booster pack and got six National League players and Mariner outfielder Al Martin. Hmmm. If I still had my fantasy-baseball-league network, I would consider trading like Mariners' general manager Pat Gillick. Or maybe I should buy a few more packs of cards. I know that in a booster pack out there somewhere, Alex Rodriguez awaits.