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Everything posted by PeteEllis

  1. @Vilham @Alf-Life Yeah you're totally right about the screenshot I used in the article, it wasn't the best angle to show the buddy-boost/climb up. The next video down in youtube (linked below) shows what happens a lot better (at 8:09). The readability primarily comes from the buddy leading in this section. There are a lot of subtleties that support it, like the negative space above the wall is only on that side of the level, where as all the other walls are blocked out, which also supports the 'lead-lighting' here as its a brighter area. We didn't want the top of the wall to be any lower (regardless of the 4m consideration for the animation) as we didn't want it to seem like the player could jump up there themselves as this would have been a worse situation - if it looks like the player can get somewhere by themselves they should be able to.
  2. Thanks very much, I'm glad the article was helpful And I'm glad the diagrams/images were appreciated as I spent a while making them! But I felt they were worth it @Alf-Life Here is a YouTube link of someone playing this encounter (I just picked the top one in the search), and its good to see they play it pretty much as I intended! https://youtu.be/iYj-nkEs1xg?t=4m35s
  3. Index: Creating a Single-Player Combat Space Part 1 Creating a Single-Player Combat Space Part 2 Creating a Single-Player Combat Space Part 3 This article is the third installment in a three-part article that looks at the considerations for creating a single-player combat space, using a walkthrough of the first battle in ‘Killzone Mercenary’ as a working example. Restricting flanking opportunities for the enemy The distances in cover were also arranged so that the enemies didn’t have a route leading behind the player. All the cover pieces were arranged so that the assault troopers could move freely between them. The only restriction was that the route from the cover point closest to the climbable pipe to the next piece of cover on the higher floor was much longer than 10 meters. This meant that the enemies would never flank the player from behind if the player stayed on the higher floor. This was good for this early stage of the level as the increase in numbers of enemies would usually be tougher to fight, but as they were restricted to the central area below the player they didn’t pose much of an extra threat. Giving the enemy flanking opportunities creates a much harder situation to deal with, which is why this wasn’t included in the opening encounter. However, if the player chooses the drop down from the balcony into the arena below, the arrangement of cover from this direction allows for flanking by both the player and the enemy. The rectangular layout of the cover positions means there is a circular movement around the outside of the central kill zone and how the player moves depends on which side the enemy can potentially flank from. If the player moves to the left corner, for example, the metrics of the assault trooper’s movement would encourage them to move away from this corner and take up positions near the far right corner. The number of cover positions versus the number of total enemies would mean that at least one enemy would have to take a position in the close right corner, allowing them to ‘enfilade’ the player. Enfilade is a military term that refers to flanking an enemy so they are positioned to have no cover from the side and are thus exposed and vulnerable. If this happens here, the player would be forced to move around the edges of the kill zone to take up another position that has a front perpendicular to that which they had been using immediately before, ensuring the player has to move around the environment and cannot stay put in one place. This is a good thing from a design point of view as it ensures the player cannot complete the battle from one position and thus it would not be a static and predictable encounter for them. The circular navigability around the central killzone Last Backup Troopers The last backup wave for this combat encounter is two assault troopers that run into the environment from a door on the ground floor to replenish the enemy count when it drops to two. This is so that the player has to manage a larger enemy count for a longer duration than if it was only replenished once it had dropped to zero. This means that the difficulty is kept up to teach the player to deal with crowds of enemies, as well as stopping the battle from becoming too easy halfway through. It is more obvious to the player when new enemies are added after the current wave is dead, which can be jarring to their immersion as it feels very ‘gamey’. It is also more realistic to introduce enemies in pairs rather than individually as it gives the idea that they are working as a team. Furthermore, the ‘Killzone’ animation system was very sophisticated and if enemies were near each other when they acquired the player as a target they would gesture to each other where the player’s location was. This meant that two troopers entering the arena would appear to communicate tactics to each other, which is not only a much more appealing enemy entrance, but also helps to make the enemies seem intelligent. The door they enter through is on the side of the map that the final exit is on; the back of the arena, or screen left to the player as they look down from the balcony. It wouldn’t make narrative sense for enemies to enter from the opposite side of the map as this stairwell was locked in the opening cut-scene. It also wouldn’t have made sense in terms of directing the focus as this would draw the attention away from the side of the map that the exit is on, which is not ideal as this is the last part of the fight. In addition, the player has always been fighting towards that direction in order to escape the building, so now to be fighting away from that would be confusing. The arrangement of the cover on the ground floor already supported the two additional troopers as they entered close to where the very first set of troopers landed. The width of the available cover here also allows the enemy to face the player’s new position. As the player is much further than 15m away whilst they’re on the balcony, the troopers can freely move around between cover positions once they’d arrived. The arrangement also needed to support a view to the door opening and not obscure the player from seeing the new arrivals. During development the position of the door was adjusted in combination with the position of the pillars for high cover, whilst maintaining architectural continuity as they were part of the support structure. The final backup troopers arrive through a door that’s visible from the balcony Last Composition The last metric we needed to consider was the composition and arrangement of the exit point. It was set at a height of 4 meters so that it supported the vault down animation height for the troopers that entered the environment from here, as well as supporting the step-up animation where the buddy character helps the player up. This final animation was used as a ‘hard gate’ for this area, which is a point in the level where once you progress past it you can no longer go back to this section. It also required the buddy to be in this position before the player could leave, meaning the player couldn’t just rush through the environment to the exit. The exit also used negative space to indicate that this was the exit in contrast to the surrounding walls. The space framed the sunlight and skybox, also using the lighter colour and tones to draw the player’s eye. Being 4 meters above the floor level it also gave the player the feeling of working upwards towards something; a sense of progression. The buddy takes position at the exit of the arena in order to boost the player up Summary When you design and create the formation of a combat encounter you have to create the layout based on consideration of the NPC types you are using. The metrics of these NPCs will determine how they move around and use the environment, so skillful placement of cover positions and other interactive geometry can influence how the enemies behave and thus how an encounter unfolds. This method of constructing a combat encounter is preferable over that of ‘area restricting’ enemies where possible, as relying too heavily on the latter can lead to exploits by the player and worse still, can lead to the AI not behaving correctly. A carefully considered level layout can also affect the difficulty without the need for altering an enemy’s default numerics, such as health, damage or accuracy. For example, only providing low cover for the enemy when the player has a height advantage will mean the player can target all the enemies at any time without having to wait for them to reveal themselves. Using high cover for enemies to run between means the player has more chance of losing sight of them thus making it harder. However, if the enemy has nowhere to run to (thanks to a cleverly designed layout) and their standard behavior of poking out of cover is to reveal their full body to the player, then this would actually make it less difficult. It is also not necessary to include every element of combat in every single encounter. Removing elements is important when you are trying to balance difficulty, for example, removing the opportunity for enemies to flank the player early on in the game means they have fewer things to worry about and consider when learning the game’s combat mechanics. These elements can be layered in at later stages of the game to introduce new encounter styles and to increase the difficulty as the player increases their skill. Removing elements also helps to dictate how you intend an encounter to be played or what narrative element you want the player to experience, such as the player being overrun with enemies and feeling desperate, or them having the upper hand and being in control. You also don’t want the player to stay static during an encounter, as this will make it repetitive and predictable. It is good to move the player around the environment to experience the combat in different ways, be it by moving the combat focus and direction the player fights towards, or by introducing flanking enemies that enfilade the player and force them to move. Moving the front and the combat focus can also help with navigating the player through the environment in the sequence you intended and help orientate them to be facing the exit or next objective when the battle ends. Go back to part 2 or continue to the homepage. Any thoughts? Check out the comments! Copyright ©Peter Ellis 2016. Killzone™ Mercenary is the property of Sony Computer Entertainment © 2013. Killzone is a trademark of Sony Entertainment Europe. Killzone: Mercenary is a trademark of Sony Computer Entertainment America LLC.
  4. Index: Creating a Single-Player Combat Space Part 1 Creating a Single-Player Combat Space Part 2 Creating a Single-Player Combat Space Part 3 This article is the second installment in a three-part article that looks at the considerations for creating a single-player combat space, using a walkthrough of the first battle in ‘Killzone Mercenary’ as a working example. First Backup Trooper When one of the two assault troopers is killed, a ‘backup’ trooper is introduced who drops into the environment to replenish the numbers. This is the first stage of ‘re-directing the front’ towards the exit out of the ground floor and first section; the climbable pipe. This assault trooper enters the environment from the final exit of the whole arena on the floor above in order to further establish this area as an important location. Two vault-down animations are used before this trooper lands on the ground floor. The longer movement and animation catch the player’s eye if they are concentrating on the original enemies ahead of them, as the new enemy’s entrance is in the top left section of the screen. The new trooper won’t shoot the player until he’s landed, or has been shot himself. This is because if he started shooting from the higher level, he would have too much of an advantage over the player for this stage of the fight. As the player also has slightly more time to target this new trooper before his landing, if they're quick enough they can shoot at him before he drops. This shifts the player’s angle to be more vertical, changing it up from the mid-level shooting they started with. An extra trooper has two animations before entering the arena at the side The landing position of the new trooper starts to shift the focus of the combat further towards the left of the screen and to the side of the environment. There isn’t immediate cover for the new trooper to use straight away, as there was for the first two troopers, which further makes this new trooper an easier target when they first enter. If the player doesn’t manage to take this trooper out at the start, the ‘front’ is beginning to move 90 degrees to the left as the available cover within 10 meters of the trooper is positioned this way (see image below). The combat fronts begin to turn with the introduction of the new trooper It was important for me to gradually turn the player’s focus using an enemy at the side of the screen as I didn’t want to introduce new enemies off screen. This is because it’s a harder combat situation to deal with which would have been too tough this early in the game. It is sometimes desirable for a designer to bring enemies in off screen depending on what they want to achieve (such as making the player feel ambushed or overrun with enemies), but to ensure the player doesn’t feel cheated it’s important to make them aware of their arrival. Depending on the game’s style and the available mechanics, there are different ways in which to achieve this. In KZM we had to consider the manner in which the NPCs announced their off-screen arrival, rather than focusing the camera on them, as the player maintained camera control throughout. For example, a rocket trooper could be scripted to shoot their weapon somewhere within the player’s view; the explosion would grab their attention and the smoke trail would indicate the direction it came from. A sniper trooper however, didn’t need any specific scripting as the red laser sight on their weapon showed where they were positioned and where they were aiming. Furthermore, their behavior was such that their initial aim was inaccurate but improved the longer they had their target in sight, i.e. the longer the player stayed out of cover. This meant that the red laser sight would pass the player if they were looking away thus grabbing their attention. Re-directing the Front It is possible for the player to target the third trooper by remaining at the starting position by the door if they choose. In order to fully change the combat ‘front’ however, two more enemies are introduced who flank the exit, forcing the player to move into a new cover position. This is because the player doesn’t have protective cover to their left side and is now vulnerable to attack. Forcing the player to move ensures that they experience the combat encounter in a different way and that the battle doesn’t become static, repetitive and boring. I re-directed the combat focus towards the exit of the ground floor by entering these two assault troopers next to the climbable pipe. The cover positions for these two troopers are two pieces of low cover (within 10m from the pipe) to either side of the exit, framing the view to it. When they take cover here this establishes the new enemy front, which forces a new front for the player and the buddy. Two assault troopers enter the environment in front of the pipe The player’s new front becomes the line of cover facing the enemy’s low cover, which is perpendicular to the original front (see image below). There are a few options for the player to position themselves across the front and this determines how the enemies move and react. The new fronts for the player and enemy No Man’s Land This part of the encounter also has a small ‘no man’s land’; an empty section of ground clear of any cover or obstacles. This ground is more risky and dangerous to cross and as such is a good way to slow the player down without artificially forcing them to; players tend to deal with the threat before crossing unsafe open ground. The reason I wanted to slow them down here was to ensure that they killed the troopers before engaging with learning a new mechanic; climbing the pipe. No man’s land between the player and enemy fronts Audio Consideration When I first started creating levels I never really considered using audio as part of the design. Cleverly designed audio can have a huge impact on the player’s experience and as such is one of the best aspects for designers to use, albeit one of the most overlooked. In this arena I had originally planned to have a large puddle of water next to the climbable pipe, caused by a leak. This was in order to have an audio indication of the assault troopers jumping down into the arena by having them splash on landing. This would give audio orientation to the arrival of a new threat and would help to grab the player’s attention alongside any graphical representation. There were also other areas of water that were intended to highlight the footsteps of any flanking enemies as pockets of water splashes are more distinctive than the standard footsteps. Although ultimately this wasn’t implemented in this area we did manage to get a similar element into the following arena to highlight the location of a hidden valve, which was an alternative method of completing the objective as well as one of the challenges. This was a pipe next to the valve that had a particle effect dripping on to a piece of metal, giving a distinctive audio cue. Although this didn’t use any puddles or influence enemy footsteps, the dripping particle effect and accompanying audio did grasp the player’s attention and helped them to discover the hidden valve. Climbable Pipe The image below shows which pieces of cover have been needed so far and how the arrangement of the combat space has unfolded.\ The cover that has been needed so far After this wave of combat has been completed, the climbable pipe is the route up from the ground to the floor above. The pipe should be in the center of the player’s view as it’s directly behind the last two troopers, but if this is not the case the buddy character helps by leading the player’s eye and focus by running to the pipe itself. He also climbs up when the player is in close enough proximity, thus introducing the tutorial for the climb mechanics. The buddy introduces the climb mechanic Second Wave After the combat with the last two troopers, the pacing of the combat slows down to allow for a mid-encounter break. This isolated period of calm is not only used as time for the player to scavenge ammo and restock before the next battle, but also to introduce the new shop mechanic and the jump ability. The pacing of intensity throughout this first arena After these mechanics have been taught it is then time to kick off the second wave of combat. The Helghast Dropship returns at this point, when the player and buddy successfully jump over the gap and end up with a view of the Dropship arriving. The Dropship arrives within the player’s view from the balcony The Dropship arrival flight path was custom created by our animation team to fit with the environment, however the resulting rappel of enemies had a specific animation height we had to consider. The troopers rappelled 15m down to the ground, so we had to take this into consideration when creating the room height, as well as the height the player was going to be at to get the full view of the sequence. The four rappelling troopers also needed specific points to land on that were clear of any other geometry. This had to be positioned into the previous combat zone between the existing cover positions; I was re-using the environment by re-purposing the use of the main space, making the level bi-directional and efficient. Assault troopers rappel from the Dropship into the environment The rappelling troopers land in the middle of the ground floor and need cover to move to. The previous front for the player now becomes the front for these rappelled troopers and the balcony on the floor above is the new front for the player and the buddy. I added two additional cover points into the center of the floor so that the troopers wouldn’t all immediately run forward to the cover on the front, but would remain staggered for a more layered combat. The new cover pieces were also low cover so that they didn’t block the view in the initial combat sequence, as well as keeping the troopers in view from the player’s elevated position whilst they’re crouching in cover. The player also now had a higher vantage point on to the enemy, being 4 meters above them on the balcony. The player’s height advantage meant they could shoot down on to the enemy and as these troopers were mostly using low cover they were even more exposed from above and thus easier to target. The high vantage point also allows the player to experience the environment from a different perspective, keeping the combat from being repetitive. The increased verticality of the player’s position also means that from this perspective (in comparison to a flatter one) it allows the player to target more layers of enemies rather than losing the target of background enemies behind foreground enemies. What’s more, the longer combat distance between the player and the enemy here is a further change to what they have previously played at the start of the encounter. The longer combat distance is also necessary at this specific point in the game as it was the point of introducing the aiming-down-sights tutorial for the second time; the first being introduced during the first pair of troopers. It also means the enemies are more difficult to hit from further away and the player is less likely to hit an enemy without aiming-down-sights. The troopers spread out more than half a screen’s width over multiple layers To balance the fight so that it wasn’t too easy a climax, the cover arrangement here allowed the enemies to spread out and cause more of an issue for the player whilst still maintaining a central position. The player would have to move their aim more than half a screen’s width to target all the enemies, so this was a step up in difficulty from the easy start with the more static troopers. Go back to part 1 or continue to part 3. Any thoughts? Check out the comments! Copyright ©Peter Ellis 2016. Killzone™ Mercenary is the property of Sony Computer Entertainment © 2013. Killzone is a trademark of Sony Entertainment Europe. Killzone: Mercenary is a trademark of Sony Computer Entertainment America LLC.
  5. This article is the first installment in a three-part article that looks at the considerations for creating a single-player combat space, using a walkthrough of the first battle in ‘Killzone Mercenary’ as a working example. Creating a Single-Player Combat Space Part 1 This article will explain how to create a combat space for a single-player campaign, using my work on ‘Killzone Mercenary’ (hereon referred to as KZM) as an example. There is already a fair amount of literature on the different methods you can use for creating a combat encounter, but I felt that none of it really discussed how to arrange the layout in closer detail, nor did they discuss where the different elements were appropriate. In my early work I tried to jam in all the concepts for encounter design without fully understanding how they affected the player’s experience. As strange as it sounds, I discovered there were times when it was better to restrict the number of elements being used to provide a much more focused and coherent experience; sometimes less is more. I will take you through an example to explain what I mean and how this can be the case. I will use the very first combat arena in KZM as it’s a small encounter where I can explain in depth what goes into even the most basic combat space. This encounter is a fight against assault troopers who are trying to stop the player from escaping the building and reaching the objective building; the ‘Halls of Justice’. I designed bigger encounters that featured many flanking opportunities and complex circular navigability but focusing on a simple encounter allows me to explain certain techniques in detail and where I purposely removed some elements to balance the difficulty and give the player different experiences. First of all I will explain two important aspects that must be considered for combat creation; AI metrics and weapon choice. I will then take you through a step by step walkthrough of this first encounter explaining in detail the reasons how it was designed and constructed for optimum player experience. Metrics The design mantra ‘form follows function’ should be the basis when creating an arena layout; that is that the arrangement of geometry should derive from its purpose. The arrangement should support the function not only of the style of experience you want to create (is it a tight corridor section with close quarters combat or an open space with multiple routes and options, for example) but it should also support the main element that makes up the combat encounter; the enemy AI. When considering the layout for the AI or non-player characters (NPCs) that will populate your environment you have to consider their metrics. These are the numerical values for how the NPCs move around and use the environment and the differences between various NPC enemy classes. This isn’t something people tend to talk about and so it can be easily forgotten or missed, yet it directly affects how your enemies will move and react. For example, in KZM the standard enemy NPC class were the Assault Troopers. These soldiers could be given patrols and animations to perform whilst they were in an ‘unalerted’ state, just like every other enemy class. However, when they were in an alerted state their behavior changed so that they used cover points to move around the combat space. The maximum distance between cover points that an assault trooper would move was 10 meters. This meant that any cover point that was further away would not be considered, so we needed to make sure when creating combat spaces which used assault troopers that there were enough cover islands so they could move around. If there weren’t, the assault troopers would just stay in the same spot and could risk looking less intelligent. The assault troopers also tried to maintain a distance of 15m whilst they were trading shots with the player. The behavior was that if the player got closer than this range, but not so close that they were in melee combat distance (5m), the assault troopers would retreat to this mid-range distance of 15m. They would also never choose a cover position that was closer than 15m to the player, so when we created combat spaces we had to make sure that there was enough variety of cover positions in the >15m range. For the production of KZM we used the ‘Killzone 3’ engine and modified it for the PS Vita. In ‘Killzone 3’ the assault troopers picked their cover within a range that was further than 25m from the player, but we discovered that this was too great a distance for the enemy to still be clear and readable on the PS Vita screen. In our modified version of the KZ engine we had to reduce the combat distance to 15m, which meant that the original combat spaces we had created using the ‘Killzone 3’ metrics also needed adjusting in order for the NPCs to still work. It is an unfortunate truth that the game metrics, be it for the AI or otherwise, can change within a game’s development, which means that your combat arenas will also need to be adjusted. Weapon Consideration The metrics for both the player and enemy weapons were also considered. As this is the start of the game we can be more certain that the player is using the default starting weapons, at least on their first playthrough, before they have earned enough credits to buy a new arsenal. Therefore, the combat distances of enemy placement were considered to be comfortably within range for the player’s assault rifle. The enemy assault trooper archetype used assault rifles that were balanced to have a short range of <10m, and a long range of >20m. This meant that their behavior was to try and keep the player within these ranges and would thus move around the environment to try and maintain this. This was important to consider when building the environment so we could determine the amount of movement the troopers were likely to perform. This is important for balancing difficulty as a moving target is harder to hit. Foreshadowing As this was the opening of the game, we wanted to make it compelling in order to grasp and hold the player’s attention; we wanted to start with a bang. If the first lot of encounters in the game only included assault troopers with nothing else to differentiate them it may not have been so compelling. Therefore, we decided to include a significant Killzone enemy vehicle; the Helghast Dropship. Of course it would have been far too difficult to fight a Dropship at this point in the game, so instead it was used as an impressive introduction of enemies into the arena using the rappel ropes from the ship itself. Using the Dropship at the end of the encounter, it was important to foreshadow its existence prior to its introduction. The level’s opening cut scene introduces the buddy character, Ivanov, and the narrative that he and the player are infiltrating the building whilst trying to avoid the searching eye of the Dropship. The foreshadowing of the Helghast Dropship Once the player has control they make their way up a flight of stairs learning how the movement works and feels whilst being in a safe environment. Once at the top of the stairs they enter through a door where they are introduced to the new melee attack which utilizes the touch screen on the PS Vita. First Wave After a successful melee attack the player enters through the door to the first combat area. The composition shows the exit of the arena in the top left third of the frame. Central to the player’s view is where the first pair of enemies enter from, ensuring that their arrival is not missed. The exit to the arena is in the top left section of the opening composition Starting on the level above, the two assault troopers vault down into the gameplay space, to give their presence a more dramatic opening than merely walking in through a door. Their animation and movement also ensures that they catch the player’s eye if they aren’t looking in the desired direction. These vault down animations were 4m high, the standard height for a room in KZM, which meant this was a metric we had for the balcony and floor above. Two assault troopers drop into the environment from the level above Once the assault troopers had landed in the arena they became a lot less mobile than their standard behavior so that they were easier to shoot because, as previously mentioned, a moving target is harder to hit. As this is the very first section of combat the player encounters in the game it was important to ensure that it was easy to get to grips with. None of the enemies were waypoint/navmesh restricted to certain areas in order to limit their movement as this could potentially lead to NPCs not behaving correctly under differing circumstances. In fact, there were only a very select few instances where we waypoint/navmesh restricted any characters in the whole of KZM; we instead crafted the environments to support the behavior we wanted from the NPCs. This was important for consistency; if you restrict areas and zones for the AI then they won’t behave consistently with what the player has learnt. This would lead to the player not being able to predict their behavior and therefore won’t be able to plan how to attack effectively. Here, in this first section, the two assault troopers took cover at two upright pillars of high cover and an overturned sofa of low cover. They didn’t tend to venture further into the environment unless the player had for some reason retreated to the edges of the level. The reason they wouldn’t move and advance on, or flank the player was because the other cover options in front of them were within 15m of where the player was likely to be stood. This caused them to be more static and thus easier targets to allow the player to get to grips with the shooting mechanics. I also chose to mainly use higher cover here so that when the enemies lean out of cover their shooting positions allowed the player to shoot their full body, which was a bigger target than when they poked their heads over the top of the low cover positions. Low cover positions are great for seeing the enemies move around and change their positions, as the tops of their helmets are visible over the top of the cover. Enemies are much harder to track when they use high cover as it breaks line of sight to them, so this is usually the harder option. However, as they have restricted cover positions and weren’t moving around in this specific situation, it was the best option to use for less difficulty. First Combat Front A ‘front’ is the perceived line or boundary that faces the enemy and is the nearest position which combat should be engaged from. The ‘fronts’ used here create boundaries between the two sides; a front for the player and the buddy character and an opposing front for the two assault troopers. This was the simplest setup to start the player off with and it only required two sets of cover points as I didn’t want to encourage the enemy to flank the player at this stage. This section of the encounter only needed these few pieces of cover (in the image below) in order to work and the other pieces of cover were actually for further waves of combat. The two fronts and the cover setups providing it It’s also worth noting that the cover object which the buddy character crouches behind is positioned further forward than the arrangement of cover that the player is drawn to. This is so that the buddy character is in the player’s view so they always see the buddy’s actions and involvement. It wouldn’t be optimal to have a buddy NPC that the player rarely saw. The buddy is also kept near to the player in order to maintain a close relationship and the feeling of being a team. Empathy is directly related to proximity between characters, so if the buddy was further away from the player they would experience a much more detached feeling towards them. Continue to part 2 or go back to the homepage. Index: Creating a Single-Player Combat Space Part 1 Creating a Single-Player Combat Space Part 2 Creating a Single-Player Combat Space Part 3 Copyright ©Peter Ellis 2016. Killzone™ Mercenary is the property of Sony Computer Entertainment © 2013. Killzone is a trademark of Sony Entertainment Europe. Killzone: Mercenary is a trademark of Sony Computer Entertainment America LLC.
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