Pawtucket-based Hasbro, the maker of the Monopoly and Scrabble board games, agreed yesterday to buy closely held Cranium Inc. for $77.5 million, its biggest purchase in eight years.

Cranium, which makes its namesake and Hullabaloo games, may have at least $100 million annually in revenue, estimated Tim Conder, an analyst at Wachovia Corp. in St. Louis. The deal may be completed in the first quarter, Hasbro said.

Hasbro, which purchased Wizards of the Coast in 1999 for $325 million, will increase its leading share of the world’s board-game market, said Gerrick Johnson, an analyst at BMO Capital Markets. Buying Cranium also allows the toymaker to rely less on sales of products tied to movies such as Spider-Man 3 and Star Wars and help it add sales overseas.

“For the small sum of $77.5 million, they have another core brand they can expand,” Johnson said. “The Cranium brand can really benefit from Hasbro’s scale and multinational distribution.” Johnson recommends holding Hasbro stock and doesn’t own any.

Hasbro chief operating officer Brian Goldner said the deal would allow Hasbro to maximize the Cranium brand and increase it in international markets.

Phil Jackson, head of Hasbro’s game division, declined to provide an estimate of the company’s board-game market share. The company won’t disclose the impact the purchase may have on earnings, he said.

Hasbro, the world’s second-biggest toymaker, fell 94 cents, or 3.8 percent, to $23.87 in New York Stock Exchange composite trading. The shares declined 6.1 percent last year, while larger Mattel Inc. dropped 16 percent.

Game sales made up 41 percent of Hasbro’s $3.15 billion in 2006 revenue and is the largest of its divisions. Hasbro also makes Transformers, My Little Ponies, Play-Doh clay and Nerf sports toys.

Hasbro can “leverage our creativity and the passionate following we have around our brand and harness with their operational excellence and financial fortitude to take the brand to the next level throughout the world,” Cranium cofounder Richard Tait said.

Hasbro bought Cranium from a group of investors including TPG Inc. and Maveron LLC, Tait said. Hasbro will also help Cranium expand into mass-market retailers such as Wal-Mart stores, he said.

Seattle-based Cranium, founded in 1998, has sold more than 22 million games, books and toys worldwide and won the Game of the Year Award from the Toy Industry Association five times.

The company’s philosophy is to “give everybody the chance to shine,” by creating games that require different abilities. Its namesake game requires players to spell words backward and hum tunes to win.

“It’s been a very innovative and topical brand,” Jackson said. “Everybody finds something that they can really excel at in their games. That’s been a unique factor in the games business.”

Proceeds of the sale will go to shareholders and pay off Cranium’s debt. The final price may change depending on Cranium’s assets when the purchase is completed. Other games include Cranium Cadoo and Cariboo.

Tait, 43, said he would stay on through the transition to Hasbro ownership, then “move on to something new, hopefully spend some time with my family and go home to Scotland” to see his parents.

Hasbro bought the Milton Bradley games company in 1984 and added Parker Brothers games through its purchase of Tonka Corp. in 1991, according to its Web site.

Johnson, the analyst, said the deal was a good fit for both companies. He said it also made sense after a tough 2007, when the toy industry grappled with millions of recalls and a disappointing holiday season.

With Associated Press reports