A rooftop party is an unusual battleground for a "secret war," but that's exactly what went down at Activision's Marvel Games event at Comic-Con International in San Diego. Hosted at the Hard Rock Hotel's ritzy Moonstone Lounge, this Wednesday-night kick-off for the long weekend's many festivities unveiled one of the most anxiously awaited comics-based video games ever, "Marvel Ultimate Alliance 2: Fusion." Rooted firmly in the world of Marvel Comics - with a storyline that springs from Brian Michael Bendis and Gabrielle Dell'otto's "Secret War" with costume designs based on the work of "Civil War" artist Steve McNiven - this sequel to the fanboy-beloved "Marvel Ultimate Alliance" represents a great leap forward in gaming, according to Activision and developer Vicarious Visions.

"MUA2" also involves a new way for players to combine various character's powers with a feature developers call "Fusion." Promised to be much more elaborate, surprising, and task-specific than traditional combo moves, this titular aspect of "MUA2"'s gameplay also led to some familiar moves in the segments screened at the event, from a Human Torch/Thing team-up that looked like a two-man napalm bomb, to an alliance between old enemies Wolverine and the Hulk in the form of a famous "fastball special."

Executive Producer Jen O'Neil helps ensure that MUA2's fusion of comic-book tradition and cutting-edge gameplay is up to par. She spoke with Comic Book Resources about what the game has in common with its predecessor, why it's even better, the philosophy behind "Fusion," and whether gamers and readers will both be equally pleased with the results.

If my own friends were any indication, the original "Marvel Ultimate Alliance" was the ultimate fanboy game - people freaked out about it. How do you top that?

Iron Man and the Invisible Woman work together for the "Fusion" aspect of "Marvel Ultimate Alliance 2: Fusion"

It's pretty tough, I can tell you. The thing is, first off, we don't want to take everything that people knew and loved in the first game away. So it's still, at the core, an action RPG. It's still the largest army of superheroes. But, yes, it's time to bring it up to the standards of 2009 and also introduce some new features. The engine itself has gone through multiple revisions. Now we're able to do things we just couldn't do on the first game. We're trying to add more destructibility in the world. We have Havoc Physics, we have a Damage Team - I mean, what a great job! "I blow stuff up." Their job is to look at objects and figure out how to blow 'em up and turn them into littler objects and create debris.

In terms of the visual fidelity of the game, we're really stepping it up. Rather than having environments that look like tiled pieces, we're putting in static meshes, so it's very unique. You feel like you're stepping into a real world when you have that uniqueness. Also, with the characters, we've really gone out of our way. We have designers who look at the construction of the costumes as work that you would put together for a movie: "How would these things actually assemble together?" With the technology now, you can really make these things come to life in a way that we just weren't able to do before. Definitely the visual fidelity has been amped up quite a bit.

In terms of the art style, what we're going for is something more realistic, more gritty. That kind of segues into our narrative. We're really taking a deeper approach to the narrative construct with this title. The game starts out in the "Secret War" storyline. You know that story and what happens - well, Marvel has done a great job in giving us the creative liberty to explore what would happen afterwards. Clearly, you've got superheroes who are misbehaving in the eyes of others, so you as a player have a choice to make. Your moral compass is gonna drive the choices that you make in the game. It's pretty deep. You can get the breadth of the story in one play-through, but if you wanna go deeper, you probably want to play through multiple times and make some different decisions along the way.

The "fusion" element, in which different characters' powers join forces in new and unexpected ways, seems to be a key point of the game - it's in the title, after all. What was the genesis of that idea, and how does it play out in the game?

The Hulk winds up and tosses Wolverine for a Fastball Special.

It's not like something that's super-new. It's always existed. In comics, characters work together. We wanted to bring that to life in the video game space. Now the technology has really allowed us to do it. We felt like this is something that was a natural next step. Gamers were waiting for it and we had to deliver. But we wanted to do something that was a little deeper than your old combo moves, where it's like one power, then another. We want to make sure that it's something that really is unexpected, that really is greater than the sum of its parts. It's cool, it's something that you want to reserve for those special moments, you know? [Laughs] There's tactical reasons why you would use it. So there are some fusions that are your smart-bomb room-clearers, and there's some fusions that are pointed and targeted that are pefect for that big bad boss that normal powers wouldn't work on.

It sounds like it would lend itself to some real fanboy moments from the comics, too - we saw the Hulk and Wolverine do a "fastball special," for example. Was that sort of thing something you had in mind from the get-go?

Oh yeah, absolutely. First off, I have to give credit to our Fusion Team, who are dedicated to exploring and creating those fusions. Of course, they draw their inspiration from the comics and the movies. We want to be as faithful to the fanboy base as much as we can.

Is there one particular aspect of the game you can't wait to see players' reactions to?

Fusion is really the big feature of the game, and it does deliver. Like I said, there are tactical reasons to use it, but for the gamer, it's not just a one-button press. Every fusion has its own unique moves, so it's like a mini-game on its own. For those of you who are into the RPG aspects, we're really trying to build that out even more. For those of you who want to just quickly jump into the action, you can try to avoid the RPG aspects if you want to. I don't know why you would... [Laughs] I like the upgrades! But we're building a game for everybody. We want to make it so the core gamer and the fanboys are pleased, but we're also making it accessible for anyone who wants to pick it up and learn more about the Marvel Universe.

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