Sound Design for an Action Role Playing Game
As a freelance sound designer, I had lots of fun working on Wolcen’s Act IV. A significant portion of my work was designing and implementing sounds for 15 brand new enemy mobs. I was also trusted with designing the audio for the final boss of the game. So I wanted to share a little about my process of designing and implementing sounds for mobs for an Action Role Playing Game (ARPG) like Wolcen: Lords of Mayhem.
Mob Categories
Mobs in Wolcen are typically divided into two categories: trash mobs and elite mobs. Trash mobs are the weakest enemies in the game. They are not very threatening by themselves but often appear in large numbers. Which has a bearing on sound design decisions, which I’ll discuss in more depth further on. These mobs are essentially canon fodder. The player can often obliterate whole swathes of these enemies with little effort. Therefore their sounds needed to be approached in a way that would convey and acknowledge these factors. Generally, I’d make sounds of a short duration without long tails. Because they spawn in such large numbers, the frequency of their attacks in groups can be considerable. It was therefore important to make their sounds short and to the point.
Elite mobs, on the other hand, are more impressive, physically larger and more threatening to the player. They appear in smaller numbers, but have more elaborate visual effects on their attacks and abilities and do more damage. The sounds for the elite enemies therefore needed to be more impressive to match their stature. Because of this I could make sounds for the elite mobs more imposing, detailed and with longer tails. They could take up more sonic space.
An example of an elite mob attack - the large circular fire explosion
Pre-Attack Sounds
Pre-attack sounds usually are triggered at the start of an attack’s animation. Trash mobs usually don’t have a pre-attack sound. Their attacks are commonly low damage and therefore low priority for the player. As they are not normally a serious threat to the player, pre-attack sounds for them would be redundant and clog up the audio mix space that could better be saved for more important audio cues.
Such as Elite mob’s pre-attack sounds, for example. Most of the elite mobs that I worked on have a pre-attack sound. Because they are much more threatening than trash mobs, it provides a useful audible warning indicator to the player when they are about to launch an attack. Which can give them time to avoid the attack by dodging or using a defensive ability. In essence, it gives the player a chance to respond to the attack by listening to the audio cue.
Imparting Identity and Lore with Sound
Concept Art for two of the mobs I worked on: The Spectre Mage and the Republic Golgoth Flamethrower
In addition to informing the player of imminent attacks, the sound design of the mobs could also impart a lot of their characteristics and lore to the player. Wolcen’s world and story has a lot of lore behind it, which plays a big part of the game. Nearly all mobs in Wolcen are grouped into different in-world game factions. The lore behind these factions helped guide the direction for their sonic palettes.
Republic mobs tend to have good equipment and are technologically advanced compared to other factions. I emphasized this by using lots of mechanical and electrical sounds that power some of their weapons and armored suits. Some of the weapons they wield include rifles, gatling guns and flamethrowers.
The Cult of Souls are an undead faction made up of various skeletons and specters. Many of their skills are based around frost, ice and soul magic. Including frost and ice in their precast sounds would therefore help indicate to the player what kind of elemental attack would be heading their way. If they were hit by one of these frost attacks they would potentially be frozen for a short duration. I also recorded my voice to create breathy sounds that were used as building block elements for their soul magic attacks.
One of my Reaper sessions for a Cult of Souls Mob - The Soul Casket
I also tried to utilize sound to inform the player about the quality of a particular mob’s weapons and equipment. For example, the Spectre Lancer was wielding a very flimsy looking spear. So I made sure my sound design conveyed this by choosing rougher, blunter metal sounds and not using smooth, resonant shing sounds - which tend to convey sharp, well kept blades.
Audio Implementation with Wwise and CryEngine
During implementation it was very important to limit the voices of mob attacks and skills that had a high rate of fire. Not doing this could lead to machine gun-like effects of certain sounds triggering repeatedly during gameplay. Which is extremely undesirable. Becoming not only annoying for the player to listen to, but clogging up the audio mix in an undesirable manner and potentially masking other important game audio.
Creating variations of the mob attacks and skills was important. I strived to create variations that walked the line of being different enough to avoid the repetitive nature of a frequently cast attack or skill, but not being so different that the player could still identify each attack or skill from the familiar sound that it made. Generally speaking, trash mobs had more variations than elite mobs because of their faster rate of attacking.
The general process of implementation went like this. Firstly, I’d set up my sounds in Wwise. Paying careful attention to the randomisation parameters, attenuations and limiting of voices. Audio levels were roughly set at this stage. The final mixing of these would come later. After I had a chance to test my sounds in the game and iterate upon them until we were happy with them.
Next, using the Cryengine Audio editor, I would create audio events and link these events to the ones I had created in Wwise. Put simply, the CryEngine audio event called to the corresponding Wwise event.
Once these events were set up, implementation in CryEngine usually happened via one of three ways. The first, and most straightforward, was putting the events trigger for my sounds in the XML file of a particular mob. Each mob had an XML file that determined most of their game data.
There are many predefined ways to trigger a sound using this method, like OnAnimStart (which would trigger a sound at the start of an animation) and OnAnimCast (which would trigger a sound on the ‘cast’ portion of a particular skill or projectile). I believe these, and other parameters were created internally for Wolcen for the audio functionality we required.
The second way I implemented mob sounds was attaching a sound directly to an animation using CryEngine’s Animation Events. This was sometimes necessary to do when precise timing was required or when the XML method was not meeting our requirements for one reason or another. Implementing in this way allows you to scrub through an animation frame by frame and attach a sound precisely where you want it to trigger. I used this method quite a lot. It allowed a lot of flexibility in attaching sounds on a very granular level which increased the detail I could achieve. This was particularly helpful for elite mobs which had elaborate, extensive and multipart skills.
The third main way I implemented sounds was via particle effects. This allowed me to attach my sounds directly to the particle effects used by a mob’s attack or ability. A sound could be triggered by any of the layers in a particle effect, allowing for fine control over sound. For example, I could attach a fire sound directly to the fire layer in the visual effects. Which would allow for precise control over that sound’s triggering and duration. We might want a fire sound to fizzle out when the fire dies, yet there are still visual effects for smoke for example. This would ensure that our fire sound stops once the fire visual effect has been destroyed. This method of implementation was often used for the damaging portion of a skill - when a mob’s skill hits the player character directly.
Sometimes, there came a situation where none of those methods of implementation would suffice. Sometimes I would come across a situation which would require programmer support. This was the case for the Electric Fences created by one of the Republic Golgoth’s Flamerthrower abilities. This skill created a new game object in the world - an electric fence that could entrap the player. Because this skill created a new entity without an XML file, or other parameters I could easily modify, I had to work with a programmer to implement my sounds directly via code. This was quite a rare occasion though.
I had a great time working on the mobs for Wolcen’s Act IV. Because I had such control over the implementation of my sounds, it really made me think about implementation first. Which informed how I approached my designs before I even started them. I also got intimately familiar with how implementing audio works with CryEngine.
Do you need an experienced sound designer for your next RPG or action game? Get in touch and tell me about your project today!
The Author
This article was written by Oliver Smith. A long-time remote working freelance sound designer dedicated to making gameplay enhancing sound for games.