December 10, 2019
MechWarrior 5 revamps the series with destructible environments, refined AI, and advanced procedural levels
Speaking to how the roughly 50-person development team has transitioned to the engine, we interviewed company President Russ Bullock and Producer Alex Garden. With it being roughly 17 years since the last single-player MechWarrior game, the two talk about their goals for the long-awaited title and discuss what they learned developing MechWarrior Online that they’ve built off of for MechWarrior 5.
The duo discuss how they built their component-based mech system, which allows them to create sophisticated and varying ‘Mech damage states. They also talk about how they created the game’s distinct particle effects, which not only look great, but allow players to identify what kind of firepower they’re going up against. In addition, the developers explain how they constructed destructible environments and talk about how they balanced procedural generation with thoughtful level design. Considering this will be the first MechWarrior game since 2002 to feature a single-player campaign, what were some of Piranha Games’ goals for the project?
President Russ Bullock: Our driving motivation was to give long-time MechWarrior fans the features they always dreamed about when those classic games were released. Back then, there were a lot more limitations on technology, and the notion of playing a MechWarrior game and traveling absolutely anywhere you wanted and freely managing your mercenary unit was a dream, along with the ability to truly destroy the entire environment while fighting in an urban setting. This is what we set out to deliver to MechWarrior fans—a classic feel with the delivery of dream features using modern technology.
Were there any past ‘Mech games that had a particularly big influence on MechWarrior 5?
Bullock: Both of the Mercenaries renditions, but also, in particular, the original MechWarrior from 1989, because it was the only one that had really let you select a location in the Inner Sphere and fly there to take on contracts from any of the Great Houses. In some ways, MechWarrior 5: Mercenaries is a successor to that great game.

What have you learned from developing MechWarrior Online that you’re building off of for MechWarrior 5?
Producer Alex Garden: First and foremost, all the technical complexities and design demands involved with the ‘Mechs and the gameplay built around them. It’s rare for games to use component-based damage systems at the level you see in MechWarrior 5: Mercenaries, and even in MechWarrior Online. Together with handling multiple independent weapons systems (all attached to different destructible components), the large scale of the ‘Mechs, and all the various attributes of the 50 plus chassis themselves—having already dealt with those elements in MechWarrior Online was a major benefit.
One of the more visible improvements is in the per-chassis damage models featured in MechWarrior 5: Mercenaries, with each component on each of the 50 plus chassis now having multiple, uniquely modeled damage states. The consequences of a battle on the state of your ‘Mechs will be on display at a fidelity never before seen in a MechWarrior title, and rarely seen in games as a whole.
Was it challenging supporting a four-player co-op campaign from either a design or technical perspective?
Garden: Our experience with developing network systems and PvP ‘Mech combat for MechWarrior Online helped lay the groundwork for how we handled four-player co-op play for MechWarrior 5: Mercenaries from a technical perspective. Design-wise, once we opted for an approach that allows up to three other players to join a host’s campaign and play cooperatively as if they were pilots-for-hire, a lot of the elements fell into place.
Alternatively, a group of four friends can go straight into co-op action outside the campaign by using the Instant Action system, which allows you to play generated missions at any level of difficulty using any of the hundreds of available ‘Mech variants, along with access to the ‘Mech loadout and appearance customization features.

MechWarrior 5 features great use of particle effects that include fire, laser, and smoke. Can you explain how you incorporated these visual elements into the game?
Garden: With the large number of weapon types in MechWarrior 5: Mercenaries, it was important for us to provide a visual identity for each when seeing them on the battlefield, so that generally, most every weapon can be identified based on its projectile or effect. The battlefield comes alive when all of these elements are in play together, pushing that feeling of being in a warzone where every stray projectile, laser, or explosion might destroy a building, blow the arm off a ‘Mech, scorch the terrain, or set a tree on fire.

For the first time in the series’ history, MechWarrior 5 will feature destructible environments. How did the studio incorporate this aspect into the game?
Garden: There’s no quicker way to fulfilling the power fantasy of piloting a BattleMech than smashing through a building and reducing it to rubble to get at the enemy on the other side. Why go around it, when I can just go through it?
As a core pillar of MechWarrior 5: Mercenaries, our approach to destructibility had a significant influence on how we designed our missions and handled combat encounters. On the technical side, we took a modular approach when building the systems, with the various building types that populate our mission spaces being comprised of individually destructible elements that we can swap out and utilize in different ways.
We’re quite proud of what we’ve put together when it comes to destruction. There have been a few occasions just in the last year where, as I was playing them, I’d wished some games had what MechWarrior 5: Mercenaries offers.
Considering the game allows players to target and destroy specific enemy weapons coupled with the fact that there are multiple stages of damage reflected on armor components, can you elaborate on how the studio handled damage modeling?
Garden: Our artists have years of experience modeling, texturing, and animating ‘Mechs for MechWarrior Online, and thanks to the existing stable of art we’ve built up over that time, we were able to focus our resources on further refining the art and going the extra step with the per-chassis damage models. The pipeline here was much the same, with individual artists dedicated to modeling out the new damage states for a collection of ‘Mechs.
From the player’s perspective, the result of all this is greater visual polish and feedback in the midst of combat and in the consequences of your engagements. Approaching an enemy ‘Mech, identifying that its most powerful weapon is attached to a specific component such as its right arm, focusing your fire on that arm, then seeing it visibly and naturally become damaged before finally getting blown off in a big explosion is really compelling. Making it to the end of a mission with your ‘Mech smoking, scorched, and barely holding together is really satisfying and stresses the feeling that you just survived some major [action].

With over 50 distinct ‘Mech chassis and hundreds of sub-variants, how did the studio approach designing and balancing all the ‘Mechs in the game?
Bullock: Fortunately, we just spent nine years developing MechWarrior Online, which being a PVP game meant every ‘Mech was deeply scrutinized on balance. Although we have much more freedom with a single-player PvE game than MechWarrior Online, it still gave us a basis to start with.
How did you leverage procedural generation to develop the level structure and various environmental biomes within the game?
Garden: We knew early on that if we were going to provide the player with the entire Inner Sphere as their playground – an area comprised of hundreds of star systems each with multiple planets and biomes – we were going to need the ability to leverage a wide degree of variation, without vastly inflating the time it would take for us to accomplish it if we were to use traditional level design methods.
With that in mind, and rather than using a purely procedural system for generating levels, we opted for a middle-ground system that would build levels using a large pool of hand-crafted terrain tiles. This approach gave our artists and level designers the ability to hit visual quality with real-looking terrain formations, and our design team the ability to generate a large number of environments and encounter areas that would play and feel different to the player.

Can you elaborate on how you developed the AI in the game? Was it a challenge getting the AI to navigate across your procedurally-generated maps?
Garden: AI was approached from the perspective of the MechWarrior (the pilot) and their BattleMech. In the BattleTech universe, chassis are typically designed for specific purposes, whether as frontline assault ‘Mechs or nimble, lightly-armored scouts. ‘Mech designs have their strengths and weaknesses, which inform how a pilot would approach an engagement. Can they tank a lot of damage or should they constantly be on the move, avoiding fire as much as possible? Should they bridge the gap for short-range engagement, or stay at a distance and whittle the enemy down with long-range weaponry? How well does the pilot coordinate their attacks with their allies, and with which weapon platforms are they most experienced? All these considerations contribute to making the battlefield feel alive with thinking entities making the best choices according to their roles and capabilities.
MechWarrior 5 will not only be the first Unreal Engine-powered game in the series, but the first title from Piranha Games to use UE4. Can you explain why Unreal Engine was a good fit for the game?
Garden: At the start of the project, there was little question we’d be using UE4. Adopting a new engine always has its hurdles, but the transition was very easy. UE4 was ideal for what we wanted MechWarrior 5: Mercenaries to be, and the project only became stronger as additional updates to the engine were released.

Does the team have any favorite UE4 tools or features?
Garden: The Live Coding feature introduced in 4.22 has been a useful tool for our engineers to quickly test isolated changes, and the Widget Reflector tool was very useful as we started to build some of our in-engine development tools that leveraged Slate. On the art side, Python support was vital to our ‘Mech pipeline and optimization work, allowing us to automate and rapidly handle batch processing for tens of thousands of files.
Do you have any development tips you can share with our UE4 community?
Garden: Be vigilant when it comes to monitoring performance over time; the profiling tools in Unreal Engine are your best friends. If you want to build something with multiplayer support, treat that decision as the highly-consequential decision that it is. It can be easy to lose focus on these two things if you’re in a state of rapid development, but losing that focus will make your life harder and the game less likely to achieve the goals you had in mind.
Also, try not to reinvent the wheel. Over-engineering or over-designing a system that should be straightforward is unfortunate if you do it once, but potentially crippling if you make it a habit.
Thanks for your time. Where can people learn more about MechWarrior 5: Mercenaries?
Bullock: MechWarrior 5: Mercenaries is available on the Epic Games Store. You can also check out the game at www.mw5mercs.com, along with on our various social channels including Facebook, Twitter, and YouTube.