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Watch Dogs: Legion is an evolution of the open-world hacker playground we have come to expect of the franchise. As part of the resurging Dedsec rebellion, you cause chaos across an authoritarian London to bring down the cities ctOS surveillance system and expose the injustices brought by private military contractor Albion.
To help you in your mission, players must find new recruits for the Dedsec hacker group. And in a first for the series, the game introduces what Ubisoft refers to as ‘Play as Anyone’ – a gameplay system that allows the player to take control of any character seen walking through the streets of London once they’re allied to the cause. With each newly unlocked character, you have access to an increasing array of abilities, perks and gadgets. Be it silenced weaponry, cloaking devices, attack drones or new vehicles, ranging from motorcycles and vans all the way to ambulances and rocket-firing spy cars.
Each of these characters is unique and procedurally generated at runtime while you play the game. In order for this to work, not only does the game require a character generation system that prioritises diversity in the makeup and style of each citizen, but also a means to create unique backstories and missions for recruitment. This results in a system that manages their behaviours and daily schedules – even when they’re not visible to the player – and is one of the most complex character simulations of its kind for an open-world action game.
We recently sat down with several of the games development team from Ubisoft Toronto to find out more about how ‘Play as Anyone’ works, including.
How the ‘play as anyone’ concept emerged and the evolution of Watch Dogs character systems.
The complexities of procedurally generating character profiles and backstories such that they feel unique, diverse, engaging but also grounded in reality.
How recruitment missions are built to be unique storylines driven by their backstories.
What influence your behaviour has on the citizens of London and how their opinion of Dedsec is influenced by your actions.
And just how deep the in-world simulation system really is within Watch Dogs: Legion.
Play As Anyone
Legion‘s ‘Play As Anyone’ mechanic is exactly what it says on the tin. As you wander around London, any citizen you see walking down the street can be unlocked and used as a playable character once you have convinced them to join Dedsec. Much like previous games in the series, scanning a character with your mobile phone enables you to see information about them. Including their name, their profession and quirky and unique information about their personal lives. But what’s new to Legion is that you can now see what value they could bring to the Dedsec initiative, they might have a buff or nerf for in-game abilities such as combat and hacking, have access to specific weapons, gadgets or vehicles or have outfits that enable easy access to environments you typically would not. Hence while you might try and break into a police station in order to complete a mission, you could instead recruit a police officer to join Dedsec and then just walk through the front door without anyone batting an eye.
Once a citizen joins Deadsec, you can then quickly swap from one recruit to another. As your collection of characters grows, you can begin to tackle missions in different ways based on the skills they have available to them. And this is the core of the Watch Dogs: Legion experience as you build your own set of recruits and pick them based on their proficiencies, or just because they look cool. But each character you engage with maintains a much more complex set of logic and internal decision making than anything seen to date in the series. When you’re not playing as a given Dedsec member – or any other character that is a potential recruit – they persist in the game world and continue to go about their daily lives: going to work, meeting friends, visiting family, dealing with their own personal issues and going home at the end of the day to get some much-needed rest.
In the closing weeks of the game’s development, I had the pleasure of sitting down with three members of Legion’s development team to learn more about how ‘Play as Anyone’ works and the design considerations that help make it a reality. Joining me were Liz England, team lead game designer for ‘Play as Anyone’, Jurie Horneman team lead programmer for the ‘Play as Anyone’ mission systems, and Martin Walsh, who is not only the technology director for gameplay and AI for Watch Dogs: Legion but was also lead programmer on Watch Dogs 2 – which was the subject of a recent episode of the main AI and Games series.
So the first thing on my mind was I wanted to know about the journey between these Watch Dogs titles. And how the evolution of the systemic and emergent gameplay that has been in the franchise since the beginning led to the ‘Play as Anyone’ concept.
Martin Walsh [Technology Director (Gameplay & AI), Watch Dogs: Legion]: It actually started right at the very beginning. It was probably the second conversation I had with our Clint Hocking our creative director, we were talking about what his vision and what he said to me was ‘what if every NPC is an open world?’. And I had watched an interesting AIIDE talk by Ben Sunshine-Hill called the Alibi generation system. So we had talked about that a little bit and we came up with basically the concept of, y’know, instead of having tons of simulated characters, being able to generate a backstory essentially in run-time for characters and we got to build on the excellent work that was done on Watch Dogs 2.
And one of the other concepts was, internally we like to call the way our systems collide ‘the anecdote factory’. The idea is you have these systemic open-world games and the way the systems come together to create these interesting experiences, these are the anecdotes generated by the factory. And for us, we came up with this idea ‘from anecdotes to stories’ and so the idea is not only did we add this deep simulation in terms of the scheduling [of NPCs] and every character has connections and lives and you can actually play as them. Bring them all the way from a character in the world all the way into a playable character, but there is also a ton of persistence that goes into that. So these characters have schedules but those schedules can change based on what you do to them or do for them. They have relationships, they have permanent memories so they remember things you’ve done for them or against them, those memories propagate to their enemies and friends.
So the more you play the game basically, the more hardened and persistent the game becomes. So whereas initially, it does start out as just anecdotes, so y’know ‘I accidentally punched this guy in a bar and the bartender got mad and it started a big fight’, but later on that’s Joe the bartender who works at that bar. We have this concept of recasting where we can take any character you’ve encountered in the game or done something to and knows about you and cast them in a later mission or story and so that’s really the coming together of those two concepts. It creates a lot of the depth and a lot of the stuff that even we still find pretty amazing honestly when we play the game.

The London Simulation
When you jump into the Deep Profiler in Legion and take a look at a characters background information, we can see much more of their daily schedules. This can include all sorts of activity: visiting locations in the open world, going home after a long day at work, meeting up with a friend or family member as part of their daily routine. Naturally you begin to wonder how deep this simulation is and whether the action implied by the deep profiler are actually executed, or is it all just a fabrication designed to make the world sound richer than it actually is. If I start following a character who is meeting a pal for a drink down the pub, is he actually going to go there?
Martin Walsh: We really made a lot of those systems for people like you who wanted to role-play or explore the lives of the characters. So almost all of it, as much as we could possibly make real, is real. So yeah, they really live at that address, they will really physically go to that address and sleep there in the night and walk out the door in the morning. Maybe they’ll take the tube to work and hang out with their buddy at the pub. That was one of our high-level directions that we wanted everything you saw in the Watch Dogs 2 profile to actually be real in Legion.
And for the most part it is, Liz [England] and the writers put together a bunch of clever extra bio things that support the story, and go along with the backstory of the characters. So if in the bio it says that [a character] meets his mother for brunch, he’s gonna meet his mother for brunch, if it says he works at this place, he works there. That was part of the challenge as well, in that in this physical game world with obviously a different time also – it’s not a 24-hour day cycle – we had to make sure that we could, as much as possible, schedule them in ways that they could physically make it to the places they were scheduled to be.

The way this is achieved is that citizens go through a procedure often referred to as ‘uprezzing‘, where they are essentially promoted from being just another face in the crowd to a character that is part of your experience in Watch Dogs: Legion. By default, a character is procedurally generated to appear in the world – and we’ll discuss how characters are created in a minute – but by and large they’re background fodder for the player. If they pass you by and you ignore them, then they will simply be deleted once you’re far enough away, but any character you interact with or has engaged in any activity that catches the players attention will be promoted into the deeper simulation. But in addition, it will also promote their personal connections: their family members or friends who have some active involvement with them in the game world. All of this results in multiple tiers of characters being monitored and maintained by the simulation.