The UK’s busiest little monsters are turning their attention to the US, and if their success at home is any indication, parents here better get their wallets ready. Moshi Monsters, the free-to-play virtual pet game from Mind Candy that has grown to become the number one kid’s brand in the UK, is in the midst of an amped up marketing program in North America.

The success of Moshi Monsters goes beyond the online game and its 85 million registered users. Mind Candy is girding the golden property it has on its hands with an onslaught of new products and licenses. Just today, Mind Candy and Activision released Moshi Monsters: Katsuma Unleashed for Nintendo 3DS, the latest in a string of successful Nintendo DS and 3DS games based on the IP. Last month, Mind Candy entered a partnership with Carte Blanche Group to create a new line of Moshi Monsters plush toys. Coming up is the monsters’ first feature film, a theatrical release in UK and Ireland that’s expected to hit other markets after its theatrical run. It opens in cinemas on December 20, giving children just enough time to pad their Christmas lists with what they see on screen. Perhaps the biggest indication of how relentless Mind Candy is going to be about branching out the IP came during Halloween, when their fruitful licensing frenzy introduced shoppers at UK supermarket giant Tesco to Moshi Monster branded oranges.

Andrew Frederick, head of affiliate marketing at Mind Candy, spoke with us about his company’s plan to grow Moshi Monsters in North America.

“Right now, Moshi Monsters is the fastest growing social networking platform in the world for kids,” said Frederick. “[In the UK] the product has really taken off virally. We see kids talking about this in schools. We got the number one kid’s magazine in the UK.”

Now, he added, “The American market is definitely a focus.”

Frederick joined Mind Candy from Disney’s online kids portal Club Penguin about five months ago to lead the charge for Moshi Monsters‘ Westward expansion. Even as ancillary products hit the market here, his focus is on growing the property’s core product, the free-to-play Moshi Monsters game. Frederick believes the virtual pet game is the cornerstone of the property’s success, as the place where children develop a bond with the game universe once they adopt their virtual pet monster. As that bond grows stronger, they want to immerse deeper into the world where their pet lives.

“When I was at Club Penguin, one of the biggest engagement points was this concept of a pet penguin,” said Frederick. “Moshi Monsters has built an entire world around pets. I think Mind Candy was smart at just figuring out this is one thing that kids really like, which is caring for pets, teaching pets, having it build characteristics.”

Moshi Monsters‘ core audience is 6-12 year olds. Like any pre-teen skewed product, attracting the interest and approval of parents is as important as targeting its core users.  Frederick says that here, Mind Candy has done a stellar job with developing a “trust factor” with parents, giving them an online environment where they can feel safe sending their children, as well as a video game to play that has educational elements built into it.

“[When] we look at marketing to kids, we’re focused on the concept of adopting your own monster, customizing it, nurturing your monster. To the parents, there are educational benefits. Kids are learning math, reading, writing, typing, budgeting,” said Frederick. “For parents, it’s also an award-winning environment. We never show advertising in the game. We never show brand sponsorship in the game. It’s a very safe environment.”

As they target American children, Mind Candy certainly has a strong base to build upon from their success in the UK. The property’s billing as the UK’s number one kid brand includes having the best-selling kid’s magazine, a top five music album, and brisk selling toys, books, trading cards and the aforementioned spinoff games for Nintendo handhelds. One of Mind Candy and Activision’s first Moshi Monsters DS games spent 22 weeks as number one on the UK charts. Even before the deal for new plush toys from Carte Blanche, Mind Candy revealed in May that it had made an estimated $250 million on Moshi Monsters‘ spin-off products alone. That’s not including revenue from the free-to-play game.

For Frederick and his team, the effort to help Moshi Monsters get a foothold here starts with Mind Candy’s first global affiliate marketing program. The company has entered a partnership with LinkShare, one of the largest affiliate aggregators whose network includes Funtomic, owner of the popular youth-skewed online game site Kizi.com.

“We have an exclusive partnership with Funtomic – their web site is Kizi.com. They’re a very strong flash game portal in the 6-12 year old space. Every month, over 20 million unique visitors go to that site. We had an exclusive partnership with them for the first month, and there were 2 million kids who came into Moshi Monsters from Kizi,” said Frederick.

Bolstering the effort is Mind Candy’s generous approach to its affiliate program. The company’s compensation rate for affiliates who refer paying players to Moshi Monsters is 15 percent, well above the average 6-10 percent in the online game space. Add to that the game’s success with converting free players to paid, which Frederick called “one of the highest in the virtual world space and the kid’s gaming space,” though without revealing the actual rate.

The official Moshi Monsters rock band

Frederick added that beyond affiliates, “We’re looking for gaming sites. We’re looking for coupon and deal partner sites like Soft Wallet, Shop at home.com. We’re doing some search engine marketing. We’re looking for bloggers.”

Eventually, Mind Candy hopes to roll out a broad nationwide marketing campaign in the US that includes TV, radio and print ads, similar to what they’ve done to grow Moshi Monsters in the UK. Frederick said the company is currently testing traditional ad placements.

“We’re actually doing a big focus test in Texas with extra TV rolling, extra radio. [We did] some live ground marketing at the Texas State Fair, which is the largest state fair in the country. We’re really trying to really hone in on Texas to see how that works, and then we’re going to look at potentially expanding to other markets.”

If Moshi Monsters gets the foothold that Frederick and the team at Mind Candy believe it can in the US, our next British invasion won’t be another moody rock band. It’ll be a band of colorful monsters born of a free-to-play video game. And what a sign of the times that will be.