Super Mario must face fire-breathing dragons, death-dealing birds and a gauntlet of other fantasy threats to rescue a kidnapped princess. But can Nintendo's video-game star handle a federal investigation?

The chairman of a House panel demanded one Thursday, as he suggested the maker of the immensely popular electronic games is using unfair and abusive sales practices to monopolize the market and keep prices high.Super Mario, as just about any school-age child knows, is one of a legion of characters in the games sold by Nintendo. He has leaped from the video screen to T-shirts, lunch pails and cereal boxes.

With Mario bouncing across a screen next to him, Rep. Dennis Eckart, D-Ohio, said at a news conference that he has asked the Justice Department's antitrust division to investigate Nintendo of America Inc. for possible violations of antitrust laws. He turned over what he called "strong evidence" found by his subcommittee.

"The question is: Has Nintendo grown so big - an 800-pound gorilla - that the rest of the world is incapable of getting around it?" Eckart asked.

Nintendo officials angrily charged they'd been ambushed by Eckart and denied a chance to present their side to Congress. "This guy is just grandstanding," said Howard C. Lincoln, senior vice president of Nintendo, in Redmond, Wash.

Eckart, chairman of the House Small Business subcommittee on antitrust, accused Nintendo of intimidating retailers to keep competitors' games off toy store shelves. He said Nintendo has used exclusive software arrangements and physical computer-chip barriers to control the market, and that Nintendo had created artificial shortages of some games.

The result of Nintendo's marketing practices, he said, is that only games licensed or sold by Nintendo can be played on the Nintendo players - thus blocking independent software publishers and inflating the costs of games to consumers by 20 percent to 30 percent.

"Nintendo right now is saying you can buy our machines but you can play only our games," Eckart said.

Nintendo is the U.S. subsidiary of a Japanese manufacturer that revived the domestic electronic game industry and now controls 80 percent of the $3.4 billion market.

Eckart raised the issue less than three weeks before Christmas, as parents of children all over the country are buying or looking for popular Nintendo games. Some of the most popular, such as "Super Mario Brothers," "Simon's Quest" and "Double Dragon," were in short supply last Christmas, and shortages of other games loom this year.

The basic game unit costs $80 to $150, depending on accessories, and game cartridges range in price from $40 to $60 each.