HELSINKI | Wed Sep 26, 2012 - Angry Birds-maker Rovio Entertainment will be hoping to prove it's no one-hit wonder when it launches Bad Piggies on Thursday, just as players seem to be tiring of the game they've been addicted to for the past three years.

The new game will feature pigs which strike back at the birds who attacked them with slingshots in Angry Birds.

A hit on app stores would give the Finnish company a boost as it looks to a possible stock market flotation next year. Some analysts put its market value at between $6 billion and $9 billion, nearly on a par with another top Finnish tech name, phone maker Nokia Oyj (NOK1V.HE).

Rovio was founded in 2003 and became a global phenomenon after it launched Angry Birds for Apple Inc's (AAPL.O) iPhone in late 2009.

The highly-addictive game helped Rovio's sales jump 10-fold to $100 million last year, a fraction of the 38.7 billion euros which Nokia chalked up.

It has remained at the top of gaming charts, with more than a billion downloads, and had 200 million monthly users at the end of 2011. That compares for instance with the 240 million attracted by offerings from U.S-based Zynga Inc (ZNGA.O), such as the Facebook (FB.O)-based Farmville.

But there are signs Rovio is losing its momentum.

Amazing Alex, the first non-Angry Birds game in more than two years from Rovio, hit No. 1 on download charts in July but has since slumped to outside the top 50, while Angry Birds Space has dropped fast from the top-grossing lists.

"Rovio needs a big hit right now. Over the past two months, Rovio's revenue-generation ability has suddenly slipped badly," said analyst Tero Kuittinen from Finnish mobile analytics firm Alekstra.

In Bad Piggies, instead of shooting with a slingshot, players build vehicles that help the characters get the birds' eggs.

The company said it was hoping the new game would breathe additional life into its brand.

"We see Bad Piggies as a long-term brand-building exercise. In three years from now we want to see Angry Birds and Bad Piggies as strong vibrant brands out there," Petri Jarvilehto, head of gaming at Rovio, told Reuters in an interview.

Rovio is also expanding into merchandising, modelling its long-term strategy on Walt Disney Co (DIS.N) by selling a range of stuffed animals and other toys, as well as branded playground equipment which then bolster branding for its games.

If successful, the company says it could go public as soon as next year, offering a possible payday to its backers. Last year, Rovio raised $42 million from venture capital firms including Accel Partners, which previously backed Facebook and Baidu (BIDU.O), and Skype founder Niklas Zennstroem's venture capital firm, Atomico Ventures.

Last year some 30 percent of turnover came from items other than games, but it is the group's on-screen inventiveness which is the crucial factor in its prospects.

"Rovio needs to re-establish its reputation for creating hits with legs (staying power)," Kuittinen said.

"There is no doubt that the pig game will hit number 1 at launch. But it has to stay in top ten for half a year to erase the doubts that the fast fade of Amazing Alex has created."