Currier armies attacked Cabot territory, while Eliot conquered part of neighboring Kirkland as open warfare broke out among Harvard College’s 12 residential Houses in a quest for campus-wide supremacy.

Such inter-House belligerence began yesterday during the first round of online Risk, a Harvard adaptation of the board game of world domination.

Based on Yale’s online version of the game, Harvard Risk—which can be played at www.CEBRisk.com—delineates 64 territories and seven continents on campus to be conquered by students playing for their respective Houses.

Each player begins with one army, except for the House’s war minister who begins with 20. Three rounds of army placements, movements, and attacks will be completed every day.

If no House obtains complete domination by Sunday, May 20, there will be a sudden death round.

Two rounds were completed last night amidst accusations of spying, resulting in a decision to give war ministers access to their team roster.

By the time the first turn commenced, 1,220 players had signed up.

One of the organizers, Michael F. Ayoub ’10, said that he thought the high student participation was partially a result of Mather House’s attempt to secede from the Undergraduate Council two weeks ago, suggesting that helped generate more interest in inter-House rivalry.

“We are very lucky that the timing coincided with the Mather secession,” he said.

“Obviously, I don’t want this to be a Harvard Civil War, but this is a friendly confrontation,” he added.

Some students complained that the game’s set-up favored the more populated Houses, but organizer Adam Goldenberg ’08 minimized this factor.

“The participation rate won’t reflect the House’s size, but how successfully each House recruits players,” said Goldenberg, who is also a member of The Crimson’s editorial board.

While the game largely proceeded without technical difficulties, at one point, the Risk Web site noted that users were accidentally allowed to create multiple accounts. Then around 3:30 p.m., in place of the scoreboard, the Web site announced, “Oops, John Drake broke the flux capacitor...give us a minute or two.” John T. Drake ’06 is the “fun czar.”

Students expressed enthusiasm and satisfaction with the game.

“I think it’s been awesome. Everyone’s getting really involved. It’s nice to see Houses show a little spirit,” said Leverett war minister Daniel K. Bilotti ’09.

The game was organized by the College Events Board, a group of 20 undergraduates in charge of planning large-scale social events.

—Staff writer Elaine Liu can be reached at liu10@fas.harvard.edu.