Madow explains most participants are women, although "spouses are welcome". The cruises' format is based on that of poker cruises, which have long been trendy among devotees of what's perhaps the West's most widely played card game.

Many point out mahjong resembles the Western card game gin rummy but is played with tiles, among other "Chinese characteristics".

"Australians love cruising, poker and mahjong," Australia-based Southern Cross Cruises' managing director Guy Leslie explains.

"In all three areas, there has been a 30 percent yearly growth. Having achieved great success with our poker cruises, it seemed a natural progression to add mahjong cruises."

The company also offers Scrabble and bridge cruises. Southern Cross Cruises' mahjong tournaments at sea have increased from one to six a year in recent years, Leslie says. "We simply market to our database, at venue tournaments, and on our website and Facebook groups."

The company has gone from advertising to Australians to now trying to appeal to the Chinese market, he says.

Grad points out marketing has developed alongside the game's growing global popularity to expand Mah Jongg Madness' business. "Years ago, the information was spread by word of mouth from player to player," Grad says.

"Of course, now we have websites, newsletters, e-mails and tournaments where hundreds of players gather and talk about the next event."

Better prizes have also played up the tournaments' allure. Madow says her approach relies on flyers and a website. "Of course, word of mouth doesn't hurt," she says.

She limits cruises to 50 contestants. "Getting to know and bond with each other is important," she says. "No one feels left out. We share tables as we enter the dining room."

As mahjong gains global popularity, industry insiders believe more players from more countries will find their sea legs and ship the game even farther from its Chinese port of origin.

erik_nilsson@chinadaily.com.cn