Team-based multiplayer shooter Overwatch is getting a sequel: and interestingly for fans, it’ll bring story missions into the game for the first time. According to Blizzard, it will also “redefine what a sequel means”. Which is quite a claim for an online shooter.

Unveiled with a crowd-pleasing cinematic trailer at annual fan convention BlizzCon last week, Overwatch 2 will introduce PvE missions in an all-new story mode, as well as a new core competitive mode, Push, a six-versus-six PvP team battle, which sees teams compete to have a robot push the map’s objective to their opponent.

Before now, the original 2016 first person shooter focused on PvP gameplay, with spin-off comic books and animated shorts filling in backstories for the popular crew of ragtag leads.

Overwatch 2. Photograph: Activision Blizzard

The story mode will follow the heroes as they reunite the previously disbanded Overwatch task force. In the first glimpse, shown at the convention, the team, led by Winston, join up in Paris to defend the city against a Null Sector invasion. It’s still multiplayer, but players will unite in co-op mode to play against the computer, rather than each other.

Set to triumphant orchestral music, and telling the story of a super-team reunion in a ravaged city: the intro feels an awful lot like the Avengers.

“It’s funny, because that story was developed before Avengers: Endgame came out. I think there are some parallels there,” agrees Jeff Chamberlain, cinematic director at Blizzard, when we speak to him at BlizzCon, following the game’s reveal.

“It’s hard not to have a sense of that,” says Lydia Bottegoni, senior vice president of story at Blizzard, on the undeniable influence of Marvel, “There’s a lot of reverence in the story room towards Marvel content.”

Overwatch 2. Photograph: Activision Blizzard

The story team have been working on the narrative for Overwatch 2 for the past year, Bottegoni says. Though they are still finessing the details, we can expect it to be similar in tone to another set of superheroes: “ThunderCats has been occasionally brought up; the whimsical feel of it,” says Bottegoni.

We went hands-on with one such early story mission at BlizzCon. It too feels like what next year’s upcoming co-op Avengers game should. The characters are individual and heroic. The world is vivid; cartoonish but not childish. The team is balanced and fun to play co-op with.

Set in Rio de Janeiro, the demo sees evil robots descending from the sky and filling the streets, which we must take down. “It’s beautiful, except for all the killer robots!” quips Tracer, as she joins the cavalry.

Our four-player group fights through the robot invaders to infiltrate the command ship they are coming from. Cut scenes bookend each section of gameplay, in which we make our way through Rio to blow up the pesky command ship and coordinate as a team to stop the metal meddlers.

In practice, the story means there’s a limit on the heroes you can use on a given mission. We have the choice of playing as Reinhardt, Lucio, Tracer, or Mei. Each member of our group can only play as one of these, so inevitably a player gets left with last dibs. But we can confirm that playing as Reinhardt and smashing through robots throughout the mission is very satisfying.

Overwatch 2. Photograph: Activision Blizzard

It’s restrictive when you’re used to maining your favourite hero, though balancing a choice of heroes with a consistent story is something the developers are working on.

“We have a story that we want to tell, and there are certain heroes that make sense to tell that story,” explains production director Julia Humphreys, “So one of the challenges that we’re facing right now is how much can we open that up to give players a choice, while still being able to tell an effective story?”

Crucially, working together in the PvE environment feels seamless. In fact, the co-op story mission gameplay comes so naturally to Overwatch 2 that it feels as if it has always existed in the series.

This could play to its detriment: it’s fun, but it’s not particularly different to the original. Considering this is a sequel and not an update, it doesn’t feel like a completely new game yet. Add to that the fact that the new maps for Overwatch 2 will also be added to the first game in a generous update, and that players’ progress in Overwatch will migrate to Overwatch 2, and the need for an entirely new game is somewhat unclear.

But the effect will inevitably be more tangible as more narrative missions are revealed – something which is still a work in progress, we are told, “We are currently in this session where we’re trying to just get the very end of the story locked in,” explains Chamberlain.

A new gameplay experience made of replayable “hero missions” will also allow players to level up characters and customise their skills to unlock more powerful moves. Plus, every hero has a new look for the sequel – a slick, tweaked makeover, conveniently ready for next-gen consoles. “We wanted to be able to get those really close-in emotional reactions from characters that we haven’t really had before,” explains technical director John Lafleur.

It’s another way Overwatch 2 draws inspiration from Marvel: “It’s really important to us that they’re recognisable immediately,” says Humphreys. “We look at other superhero characters – Iron Man’s had a lot of different looks over the years, whether that’s in the comics, or across the different Marvel movies, but every time you look at him, you know that’s Iron Man. There’s never any confusion. But as a fan, there’s a lot of excitement to seeing how that character has evolved over the years. And I think that’s something we’re really excited to do with our heroes as well.”

The makeovers serve a purpose in storytelling, too. “This is taking place at a later point in the story – Reinhardt has upgraded his armour; Genji has decided to put on some clothes,” adds Humphreys.

With the new Overwatch 2 plot, and in a nod to its Marvel inspiration, Chamberlain hints that we could even see the universe expand to include a full, animated Overwatch TV series in the future.

“We talk about it,” he says. “Right now, our focus is entirely on supporting the games, but it doesn’t mean in the future, if something came up, we wouldn’t be excited to jump on that opportunity. Stay tuned.”

• Overwatch 2 will be released on PC, PS4, Nintendo Switch and Xbox One, release date TBC.

• Rebecca April May attended a press event in California, with travel and accommodation paid for by Activision Blizzard.