As Batman fans wait for the release of Christopher Nolan’s “The Dark Knight Rises” next year, Warner Bros. is serving up a Bat-quel of another sort to keep them engaged: “Batman: Arkham City” launches next week and aims to bridge the long gap between films while nurturing an emerging videogame franchise.After “Batman: Arkham Asylum” sold 4 million copies worldwide to become a sleeper hit, Warner Bros. Interactive bought gamemaker Rocksteady last year to produce a much larger follow-up and give it the kind of high-profile rollout WB typically provides its tentpole pics. WB took over San Diego Comic-Con in July with massive bannersshowing off the title’s characters. And as New York Comic Con kicks off today, an extensive marketing campaign is rolling out that involves pricey ad buys covering TV, print, radio, online and pair-ups with promo partners. For example, Toys R Us hosts a launch event next week from its Times Square store, while Walmart, Best Buy, GameStop, nVidia and Samsung will cross-promote the game with their own advertising efforts. WB has also let its consumer products arm play with the property, releasing toys from Mattel, batarang-shaped videogame controllers from Bensussen Deutsch & Associates, Hallmark cards and apparel from Converse, Ecko Complex, C Life, New Era and Briefly Stated. DC Comics will publish a comicbook tied to the game, while WB’s inhouse record label, WaterTower Music, is producing the soundtrack, featuring new songs by bands including “Panic! At the Disco.” And WB is plugging its acquisition of Flixster and backing of UltraViolet by giving away a copy of the “Batman: Year One” DVD with every purchase of “Arkham City.” The game’s launch “is something all of our divisions internally are participating in,” said Martin Tremblay, president of Warner Bros. Interactive Entertainment. Tremblay said the release of “Arkham City,” produced in a quick two years after the first, falls in line with the tentpole strategy Warner Bros. Interactive formed in 2007 of making games that can be treated as major franchises for the studio. WB has been producing Batman games for decades, but since they were licensed to outside gamemakers — and normally tied to the release of a Batman pic — the studio didn’t feel the need to spend much time developing them. “Now that we have taken Batman back home and are self-publishing, we are taking care of it and treating it the same way other publishers are treating their own (intellectual property),” Tremblay said. “We are treating Batman as one of the big pillars of our company as we go forward.” Buying Rocksteady was part of that move. Warner-owned DC Entertainment gave Rocksteady free reign to play with the characters and tell their own Batman story independent from the films and comics. While the first “Arkham” game featured 15 hours of gameplay, the sequel runs 40 hours, developers said, enabling them to add Batman villains like the Joker, Harley Quinn, Catwoman, the Penguin, and Riddler, along with heroes like Robin and Nightwing, to keep the story interesting, said Jamie Walker, studio director at Rocksteady Studios. While Nolan’s Batman films are more grounded in reality, Rocksteady’s version is even grittier. “There are so many interpretations of Batman,” Walker said. “Working with DC let us portray the characters in a more realistic way and tell a unique story,” Walker said. “They have needs and flaws.” Key in “Arkham City’s” design was working off the foundation of “Arkham Asylum” and giving players the feeling they are Batman. “We did everything we could to push that concept forward,” Walker said. “Every character pushes that button.” Walker recalls a test session in which a gamer perched Batman on top of a gargoyle and scanned Gotham. “He sat there for 10 minutes not moving,” he said. “We asked him if he was OK, and he said, ‘Yeah, I’m Batman.’ That’s exactly the kind of reaction we’re going for.” As for the promo push, “We know we have the hardcore gamers expecting the game, but the main goal now is to reach out to mass consumers who may not be familiar with it,” Tremblay said. Trying to reach two different types of gamers requires publishers to start hyping titles nearly a year before release. “In today’s world, releasing a game is about managing the community that is excited about the property,” Tremblay said. “That often means entertaining people with how we’re progressing with the release of a game. The community is asking for it.” Walker has been surprised at the sheer scale of the “Arkham City” campaign but understands the need for it. “Game marketing more and more is treated as an entertainment event,” Walker said. “That’s something that happened fairly recently. Games were advertised to people that only played games. But now that games have gone mass market, we have different messages for different audiences.” With pre-sales already topping estimates, WB believes “Arkham City” could at least double the 4 million units sold by “Arkham Asylum” worldwide. The game is easily one of the more high-profile titles — including “Gears of War 3,” “Rage,” “Uncharted 3: Drake’s Deception,” “Battlefield 3″ and “Call of Duty: Modern Warfare 3″ — the videogame biz is counting on to boost sales after months of decline. WB doesn’t want gamers to lose interest in “Arkham City” after it’s released. It aims to keep them occupied with fresh digital content that will offer up new characters to play, like Nightwing, and downloadable levels, for example. “We want people to play this game for a long time,” Tremblay said.