Designing Assassin's Creed II - Prima Games

Designing Assassin’s Creed II

by Prima Games Staff

“Let’s say that you’re faced with a game where you need to develop more than 230 features with the use of a production team of over 300 developers in a schedule that didn’t allow any revision of your design, and that at the end, your game must be commercially successful and critically acclaimed. How do you do it? That’s what I had to face with Assassin’s Creed II.”

It’s GDC 2010, and Assassin’s Creed II lead designer Patrick Plourde is giving the final presentation of the entire event: an hour-long insight into the creation of one of 2009’s most excellent games. Ubisoft’s sequel manages to do what its predecessor couldn’t – it combines superb openworld technology with deep, involving, rewarding gameplay.

Part of the recipe for the game’s success in this regard actually came from a directive from upper management, and not only that, but it arrived some months into the game’s creation, further adding to the immense logistical challenge.

“Yves Guillemot came up with the idea that Assassin’s Creed II needed to be a ‘monster’ game – a game with so much stuff to do in it that it would overwhelm the player. We could have all the resources we wanted to achieve this vision,” Ploude says.

“With that mandate, we returned to the drawing board – digging up ideas that were canned, like the Villa, and coming up with new concepts that would be handled either in Montreal or in other studios, like the Assassin’s Tomb, the Database, the Truth Puzzles and the Flying Machine. It didn’t simply add new features, but it also changed a lot of the story and the characters. Mario Auditore suddenly became the owner of the Villa, and a very different character then originally imagined.”

This notion of overwhelming the player with content was all part and parcel of the plan to eliminate what some say is the repetitive nature of the original Assassin’s Creed, and virtually all reviewers agreed that in this respect, AC2 more than delivered. The flawed mission structure was gone, replaced with a new series of objectives that proved to be far more compelling to the player than the original game’s.

However, in addressing the shortcomings of the first game, Patrick Plourde plays down the notion that its repetitive nature was actually the problem. Instead, the missions actually took you away from the elements that make the Assassin’s Creed experience so cool, explaining why the gameplay was not as satisfying as it could have been.

“A lot of times people said that the missions were repetitive. I don’t necessarily believe that. Every game features repetition. Nobody says Tetris is repetitive because blocks are always falling down!” he says, laughing.

“But the thing is that the missions didn’t challenge the player on the core gameplay. We’re inviting him to be an assassin yet the missions were more like mini-games. You’d sit on a bench and press Y and the mission was over. Wherever you end up, they’re a little bit boring. It didn’t translate well. The worst thing was that since they didn’t use the core gameplay we actually had a team to code those features so it was really hard to develop.”

In designing the mission structure for ACII, Plourde and his team went back to basics, looking to make sure that all elements of the new game were based around a strong core structure of three major features. The first of these he identifies is the fighting system.

“Our fight system is different to other games on the market: it’s based on timing. We embrace that. It’s not combo based. It’s not Ninja Gaiden or Bayonetta or anything like that,” Patrick explains. “It’s really focused: you need to wait for opportunities, there’s a certain flow to it.”

Combat is very much context-sensitive in that it relies on the attacks made by your enemies. In the place of combo strikes are precise, deadly one-hit assaults.

“The other combatant is a powerful element as I’m using his movement for my attacks. For ACII we wanted to keep the same base but add more tactical choice,” Plourde says.

“What we mean is adding new moves, designing new enemies that would challenge certain behaviours and more tools. With that we felt that the player would have enough choice to make the experience fun for the 30 hours in the game we were developing.”

Spears, axes and blunt weapons were added to the mix along with new disarming techniques, while all weapons were gifted a full range of attack moves. Grunts, seekers and agile opponents skilled in evading attacks were a new inclusion designed to introduce more variety into the battles and to challenge the gamer in different ways.

Video: An encore showing for Digital Foundry’s video love letter to AC2. This time-lapse video demonstrates one of the new features added to the sequel, the day-night cycle.

The second main gameplay pillar that the Assassin’s Creed II team concentrated on was the navigation system. The free-running aspect of the game is clearly important, but Plourde feels that criticisms of the implementation miss the point.

“Sometimes – a lot of times – you go on the forums. They say there’s no challenge, you just hold down two buttons, that’s it, the system does everything automatically,” he observes.

“There’s a reason for that. It’s a conscious decision because we want to focus our movement on fluidity. The challenge doesn’t come from the input, it comes from the environment. When you look at a district of Venice from above, it’s like the environment is a rat’s maze. It’s extremely complex to navigate… it’s not just 2D layout, every surface is climbable in the game. So the challenge for the brain is to map that matrix – that’s where the players are challenged.”

It sounds very much like an attempt to make the game more accessible to more players, by removing the notion of lightning-fast finger reflexes for the free-running, and instead “re-mapping” the task to something that anybody can tackle. New enhancements were made to the movements of the assassin to ensure a more fluid, faster response, particularly in scaling the structures in the game.

“If the movement is fluid enough, players aren’t going to think about the second-to-second button presses,” he explains. “They’re thinking about using the matrix to escape the guards as fast as they can because that is the best way to get out of the situation. Or, I need to get to the top of that church and I’m analysing the climbing points so I can reach it.”

The final pillar of the ACII experience is defined by the development team as “social stealth”.

“AC1 introduced a system which really is revolutionary. Instead of using light and shadow to make you invisible to enemies, it’s your social behaviour that makes you invisible,” Plourde reckons. “If there’s a killer in the room, nobody’s going to know he’s a killer until you see behaviour that isn’t normal. It’s that concept that we’re exploring in Assassin’s Creed.”

However, the basic idea was somewhat under-developed in the original game, with the player able to switch in and out of stealth with a single button press. Altair put his hands together and prayed in order to blend in. The team looked into using the multitude of NPCs in the game to produce a more compelling implementation.

“In ACII what we wanted was to use the crowd as a gameplay tool. In AC1 we had that nice technology where we could display 150 NPCs on-screen so it looks really impressive but each one of those 150 NPCs would be there just to make your life miserable,” Plourde says.

“You’d bump into them, they’d jump and scream, guards would detect you, and bad things would happen. What we wanted was to change that and use the crowd for something that is positive for the player. We’d use it to blend and while it’s still visually impressive to have 150 NPCs on-screen they’re also there to help. Visually it’s really nice and there are now gameplay opportunities.”

The development team aimed to concentrate on the three gameplay pillars in all aspects of the mission structure.

“If you compare it with ACII where you have the Assassin’s Tomb levels… they’d focus the challenge on navigation. After the first prototype it was really obvious that it was fun. It felt right for Assassin’s Creed because it was challenging the player on one of the core pillars of the game,” Plourde observes.

“It didn’t require any extra lines of code to do those missions because it used the basic behaviour of the assassin. This is really important. Not only are you going to end up with something of a higher quality but you’re going to save time if you use your main gameplay as the base of the missions.”

In addition to the pillars, ACII features what the team described as supporting features that gave meaning and depth to the core game, along with what were termed “exotic” elements designed to switch up the pace. The other features could be less polished, so long as those crucial pillars were the best that they could possibly be.

“Every time we made a tweak to one of the three gameplay pillars and we went to playtest, the impact we had in terms of fun was greater than even if we implemented 20 other features,” says Plourde. “It was really noticeable. So the thing is that other features can have less polish and you’d still have a really great game. The important thing is to not cut them.”

Patrick uses Mass Effect as a case study in how supporting features didn’t need to be as brilliant as the core gameplay in order to still provide value and entertainment to the player.

“So you have the Mako and you go on that vehicle to visit planets. If they released a racing game with the Mako it would be the worst game ever,” laughs Plourde.

“The mechanic of it is not that great but visiting a planet is something on the side and removing that – for Mass Effect 1 at least – would reduce the game to five maps with a linear corridor. You’d remove the feeling that the world is huge.”

Less important features can still contribute to the overall whole in a meaningful manner, but with Assassin’s Creed II there were over 230 different elements. Not all of them had to be brilliant, certainly not up to the polish level of the pillars.

“When I finished Mass Effect I’d still had a good experience because the core of their game – the RPG elements and the dialogue – were extremely polished so I didn’t have a sour taste in my mouth because the Mako wasn’t great. It’s important that you remember where your core is then the rest can be something that isn’t 100 per cent perfect.”

A good example of this within ACII is the economics system. Renovating your village and filling your attic with priceless works of art is a cool addition and it does serve the gameplay too in that you can add to your equipment levels, but it’s clearly not a central aspect of the overall game package.

“We have the economics system and overall it lacked depth compared to something like EVE Online. There’s no comparison between the two,” Plourde states with a smile.

“But for Assassin’s Creed it wasn’t important because it wasn’t a pillar. If we were using the economic system in our game as a core pillar it would’ve appeared shallow and frustrating. If players would have to grind for money in Assassin’s Creed, at some point they’d say ‘What the f***?’ yet if you treat the same system as a reward it becomes positive in the gameplay experience. It makes the world bigger, everything feels right. It’s because we didn’t challenge the player on that as part of the core gameplay.”

You might think that assassination itself would be one of those core gameplay pillars, but it isn’t. It’s simply the culmination of using the fighting system, the navigation and the social stealth in concert. It’s the payoff for all your hard work.

“Assassination for us on ACII is the end result of the player using the core gameplay within the confines of the fantasy,” clarifies Plourde.

“So basically I have a target to kill. I’m going to be challenged on the core gameplay which is navigation, fighting and social stealth to reach a target and once I’ve reached it, I press X, he dies. And so basically the design direction was to have no challenge in executing them and really the call is that life is cheap in Assassin’s Creed.”

The process of assassination in the game was also changed, tweaked and refined from the first outing due to frustration from some of the audience.

“That’s something we received back in feedback from AC1, that sometimes it’s hard to perform an assassination,” Plourde reveals. “You’re supposed to be the master assassin, it’s not supposed to be hard. Assassination is now perceived as a reward for the player.”

Assassin’s Creed II was a truly mammoth production, featuring over 300 staff that worked across several continents: Ubisoft Montreal handled the core game, the Singapore studio took care of the linear missions while Ubisoft Annecy in France implemented the villa.

This presented something of a unique logistical challenge. As lead designer, Patrick Plourde admits that he can’t remember half the names of the people who contributed to the game, and as many of these people would be working in other countries, he couldn’t visit their desks to communicate his ideas.

“You, as a designer, you have to be sure of what you’re making. You have to have the courage of saying ‘this is the game we’re making’, understanding it and basing those decisions around that,” Plourde says. “How can you communicate that efficiently to your team? With a strong document process.”

Plourde points to three major advantages of strong documentation. Firstly, by having ideas committed to paper, you’re forced to think them through and it makes the process of identifying flaws that much easier. Secondly, the mere act of documenting everything means that you’ll never forget an idea. And finally, it reduces the scope for unnecessary questions from other sections of the team.

“By saying it limits questions I’m not saying that I don’t want to have comments or feedback from anybody in the team. Everybody is invited to my desk and come up with suggestions, I’ll listen to any comments, I don’t think there’s a bad idea,” Plourde adds.

“What I want to say is that I don’t want a programmer to spend half an hour, 15 minutes, five seconds on a question that could be answered by yes or no. The programmer is there asking ‘does the designer want this blue or red?’ I want them to have some kind of spec, knowing how to make that decision on the fly, and focus his work on what he’s good at – which is writing code. That’s what he likes, that’s how you can maximise everyone’s effort on your team.”

But the final element of the documentation process is the most crucial in a project where every feature you produce has to be right on the first pass.

“It costs less to fail in documentation than in production. When we have to review game design documents, it’s better to do that than to revise three or four weeks of work by a games programmer,” says Plourde.

He isn’t into game design bibles either, and feels that documenting an explanation of concepts or gameplay ideas doesn’t help the programmer in his day-to-day life writing code. In putting together his design documents, Plourde talked to the team to see what they wanted from them, what would be the most use.

“We made the design documents with the help of programmers, we asked them what they needed for us to give them,” he says.

“We separated every feature: what happens in the gameplay loop, what happens in spawn/despawn, what’s the control, AI reaction, sound etc, and in every one of those cells we would write lines and every line needs to have an answer to a question – does it work? Yes or no.”

Many of the game’s variables are highlighted in the document with brackets. These contain suggested values for a huge array of aspects of the gameplay – for example, how long it takes to loot a corpse.

“Everything in brackets is a value we want to have available in data, so those figures are not hard-coded.

“Those variables are available to game designers at their desks so they can tweak their values and play with them in gameplay. It’s really useful late in production where you want your programmers to debug the game and you want your designer to polish. So when I said we had no time for revision, we had time to polish our mechanics using variable data, and also it removes needless debates.”

In a team passionate about their work, discussions and arguments over about minutiae can cut heavily into production time. The variables system allows the team to playtest rather than debate.

“The fun isn’t in the document, it’s created in the game, so when you use brackets, you’re trying a value in the game,” Plourde says. “It also helps communicate to the programmer what’s important for you as a designer in the feature.”

The ACII team was fastidious in its work with the design documents, keeping them scrupulously maintained right up until the final days of production.

“Right now you can go into the database of documents for ACII and it’s what we shipped with. It’s really important because if people start mistrusting your document, they’re useless,” Plourde states definitively.

“The programmer’s going to ask himself a question: ‘Is that really what the designer wants? Did he change his mind recently?’ We don’t want people to ask these questions about what they’re supposed to do. We just want them to do their stuff the best they can.”

Five designers produced over 200 documents in creating Assassin’s Creed II, and the process worked to such a degree that out of the 230 features devised, only one of them – the Notoriety system – received a second revision. The to-the-point nature of the documents, combined with their sheer depth, also meant they could be used by the testers in the QA department.

“Their testing was all based on our design documents. If the line didn’t work, they’d file a bug and that’s it,” Plourde says. “It was really useful in production because when I said we had a team of 300 in production, I didn’t include the testers. They were in Romania!”

So the basic design work in Assassin’s Creed II was strong enough and flexible enough to ensure that the features didn’t require wholesale changes or second revisions. But this is not to say that the team did not work intensely on refining the game using that versatile framework. Playtest was an enormous benefit in this respect.

“ACII production meant we had zero time for polish. I’m serious when I say we had zero time to polish the game,” emphasises Plourde.

“We made the gamble where playtest would be the main tool for identifying problematic areas in the walkthrough and would actually be the tool that would make sure that our game is polished. It was going to be playtest that would flag every issue we had in the game and if we solved those issues, we would have a really polished game.”

Reams of data would emerge from the playtests that the team used to tweak the balance of the game. How long it took for players to complete missions, where the player died – quantitative data along those lines was instrumental in discerning where gamers weren’t having fun.

“Sometimes you’d say to a mission designer that this map is too hard and he’d say ‘You’re full of shit! You suck!’ By having concrete data, showing that the player died 15 times in this mission, it’s not about two people’s taste, it’s about what happened in the game,” Plourde shares.

The second important conclusion from the playtest is more qualitative in nature, an appreciation report if you will.

“This context data is the most important. If somebody says that a feature is super-fun but it’s not exactly what I had in mind about that feature, I don’t care. It helps provide perspective to your work,” reasons Plourde.

“Knowing what happened and what the players had in mind when that happened, that helps you make decisions that make sense. You need to adapt those playtests and what’s going to happen in them based on your production cycle.”

The two major stages in production are pre-alpha, where the feature being built is put to the test to validate whether it’s working as intended, or not. Post-alpha, the feature itself is locked and the objective is to make the experience as smooth and as fun as possible.

Going back to the core gameplay pillars, the navigation system was one of the key elements put through playtest to make sure it worked and that it was as much fun as it could be.

“Our buildings went from one or two storeys high in AC1 to three to four in Venice,” Patrick explains. “The thing is because we wanted to have more distinction between every city, the problem was that climbing felt very slow and the player didn’t use free-running as much as we would like in the game.”

The team were faced with the prospect of one of the core improvements to the game simply not working to the degree that they wanted it to. Re-mapping the layout was a production step too far and would have worked to the detriment of what the designers wanted to achieve with one of ACII’s core improvements.

To gauge the effectiveness of the navigation, the team created overhead heatmaps of the environment to show how much of the layout is being used in gameplay. As Plourde says, more navigation means more fun.

“We have two players in the same playtest in the same mission, sitting next to each other, breathing the same air, eating the same food at lunch and player 12 found the mission boring while player 13 found the mission fun,” says Plourde.

“You can really see in their behaviour that one player really maximised the navigation and found one route, while the other one fooled around a bit more in the city and it affected how they perceived the same mission.”

The heatmaps proved to be enlightening. They showed that on the one hand one of the players was investing every nook and cranny, and thus maximising the return on the investment in the artwork.

“But at the same time I was looking at it again and panicking because ‘Arrghhh! Nobody uses the rooftops!’ There are rooftops with two hours of gameplay and nobody was visiting them at all. We had already said that more navigation was more fun, but they’re not using the rooftops except where the mission required it. In that case, in mission 10 of Sequence 7, it was rated the most fun mission by players. So it proved that more navigation equals more fun in Assassin’s Creed.”

It turned out that the casual players weren’t getting to grips with the navigation system, while the gamers that were perceived to be more “hardcore” by the team were maximising the potential, appreciating it a lot more and getting more fun from the mission.

“The decision was made not to change the layout. Why? Because hardcore players didn’t appear to have any problems so technically it was functioning well,” Plourde reveals.

“Secondly, our first city that the players would see in the game – Florence – had lower buildings. So once the player reached Venice, the last city in our game, they would be acclimated to free-running. That was the educated guess that we made… that casual players who reached Venice would become what we would call a hardcore player. They would think that the navigation was fluid enough.”

And that fluidity was key, leading to one of the most crucial improvement to the parkour system. Taller buildings meant that they took longer to climb, and the feedback from the playtest was that it just didn’t feel right. In the original Assassin’s Creed, players would climb, then return to a neutral pose before being “allowed” to climb again. In ACII, this was refined with the neutral pose removed, to facilitate what the team called the “strong climb”.

“The character would then reach the rooftops twice as quickly as he did in AC1,” says Plourde.

“So if you have a four-storey building, you have the same speed as you would in reaching a rooftop in AC1. We also made a change to the environments in that every free-running path would lead to the rooftops. So players would start do the free-running and the designer would guide him to the rooftops and to happiness!”

A more difficult challenge that arose in the playtest was the concept of using the crowd to blend. To put it simply, despite the design feeling “right”, the gamers just didn’t get it, and thus didn’t use it.

“The system worked, I’d play it at work and it worked for us, we understood the matrix, yet people didn’t understand it,” Plourde says with frustration.

“It was really simple – you hold the B button when you’re next to a group and then blend – you walk automatically within the group. People didn’t understand it at all… We had to find a solution. When people say that playtesters are going to come into your building and say nice things about your game because you’re the developer, it’s not the case! Blending was rated badly by players.”

The idea came to make the blending system completely automatic, activating on its own depending on your proximity to the crowd. However, the coders weren’t happy about the prospect of rewriting an important system within the game. The solution turned out to be astonishingly simple.

“I’m at my desk thinking, why don’t the players just hold the B button? It’s that simple!” Plourde remembers.

“So I taped the B button down. It’s automatic, and it works… it took maybe two hours to code in that cheat so that when you’re walking you’re just automatically holding the B button. The thing is, as soon as we implemented that, the player impressions on blending changed from something that was bad to something that was good, so we’re really happy about that. Not only that, but every mission that required the player to be stealthed had the difficulty lowered and the fun factor raised.”

Plourde’s final example of how valuable playtest is didn’t have a happy ending. User feedback on the fight system – one of the core gameplay pillars – showed that the player thought that the whole process lacked variety.

“We know – because we tracked what he did – that he didn’t use all the moves,” Plourde says, explaining the result.

“So what we did was compare his results with one of our designers who knows the system. You really see a difference in the usage and that’s how we perceive the fight system. The problem is that we didn’t find a solution and it shows in reviews and appreciation. If there’s one thing people are talking about, it’s how the fight isn’t as focused as it could be and that’s where we failed. I just wanted to give that example to say that when you’re going through playtest, sometimes you can analyse it but you’re not necessarily going to have a solution for it. But at least in case we have a sequel (located in Rome!) then you’re going to be able to solve it.”

So, 300 developers, 230 features and zero scope for revision. Now you know how the team did it, and presumably those same systems are in place for that Rome-based sequel, due at the end of this year.

Concluding his GDC presentation, Patrick Ploude talks in broad brushstrokes about the lessons learned after his years in making the Assassin’s Creed games.

“In making big-budget games, mistakes can prove extremely costly. If you start derailing a 300-man production it can go wrong really fast,” he shares.

“Also it leads to lower quality if people work on stuff that isn’t going to ship. It creates needless work, lower morale. Go to a programmer who worked really hard on a feature for two months, cut it, and then tell him this is a new feature you need him to work on. See how he’s going to react. That could lead to a lot of fail.”

“Designers can lower that risk by looking at what’s in the core of the game, and building around it, providing the art team with strong documentation that fits their production needs, and maximising the playtest to validate decisions and to make informed calls. And with that, in the end, we produce the anti-fail!”

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