Cult of the Lamb was a breakout success this summer, selling more than a million copies in its first week. Through its unique premise, Massive Monster’s dungeon-crawling, base-building, rogue-lite hybrid casts you in the role of a possessed, cult-leading lamb.
Your mission? Indoctrinate woodland creatures, perform dark rituals, and hunt down bosses – all to appease an eldritch being, The One Who Waits, and become leader of “the one true cult.” A major factor in the game’s success is its compelling gameplay loop, which reviewers have described as “addictive,” “satisfying,” and even “perfect.”
We sat down with Jay Armstrong, Massive Monster’s design director and lead programmer, to discuss how the team chose which genres to combine, what they did to balance a two-genres-in-one-game approach, and their top tips for overcoming challenges to keep development focused.
The Massive Monster team – Jay Armstrong, Julian Wilton (creative director), and James “Jimp” Pearmain (art director) – is spread out across Singapore, Australia, and the UK. How did you all meet and start making games together?
We all started making Flash games individually. We first met through the Flash game scene, forums, and events. We all worked together on different games, and when Flash games fell away, we decided to team up and make games for desktop and console.
The first game that Julian and I created together was called Super Adventure Pals, and almost exactly 10 years later, we released Cult of the Lamb. So the three of us have been collaborating together for a long time.
What was your source of inspiration for Cult of the Lamb? How did you develop the idea?
Funny enough, the cult stuff didn’t come until much later. The game actually started with the idea of combining the genres of a roguelike with a colony sim/base builder. I noticed that games like RimWorld and Enter the Gungeon created so many interesting emergent narratives – stories that spring out of the game’s mechanics – that made it so everyone’s experience with the game was unique. I was excited about the idea of combining those two genres to create something that would become more than the sum of its parts, so I created a prototype that I planned to show to the other guys at an upcoming PAX.
When I took it to Jimp and Julian, they loved it, but we immediately found that it was a really hard game to pitch when talking to publishers. At this point we still hadn’t come up with the cult theme. We knew we had to figure out a way to market the game in one sentence. We needed a player fantasy we could explain easily and that people would immediately understand. It took around nine months of experimenting with different themes before we finally landed on the idea of the cult.
Once we had that, everything for the next three years was about making sure we kept hitting the “promise” the game’s theme created. The game had to feel like you were leading a cult, which meant we had to have rituals and sermons. But figuring out how to make those game mechanics took a lot of iteration and experimentation. We got very used to cutting ideas that didn’t achieve that goal, and “listening” to what the game wanted to be. Having a clear goal for what we wanted the experience to be meant we were all on the same page, and it was obvious when something was or wasn’t working.
Cult of the Lamb is your first Unity project. Why did you choose Unity to develop it?
Yes, Cult of the Lamb is our first Unity project. We chose it because of the great tools it offers for iterating, quick testing, and allowing designers to lay out levels. In the past, we’ve created our own editors, but the tools that are available for Unity and on the Asset Store are such timesavers. We also have the flexibility of building whatever tools we want for ourselves.
How did Unity enable you to manage the game’s combination of 2D and 3D assets to create a 2.5D look?
One of the reasons we picked the 2.5D look was because we were moving to Unity and it was our first time using a 3D engine. It felt like a waste if we just stuck to normal 2D, so we decided to take advantage of that extra axis!
It was great being able to move the sprites around and create faux-3D structures; to use the Editor to decide on the best angles for our characters and the camera.
Why did you choose the top-down perspective? What were some challenges you encountered during implementation and how did you solve them?
The main problem with our perspective was that we had to keep the camera relatively fixed, which restricted our options for combat and the placement of things in the world. While it is sort of top-down, we had to arrange things so that the important stuff was all at the top/back of the screen. It was fine once we got the hang of it: Creating restrictions forces you to come up with creative solutions.
What benefit did Unity’s lighting provide for creating the look of Cult of the Lamb?
The lighting is such a big part of what makes Cult of the Lamb look so cool! We had some support from our extremely talented friend Jonathan Swanson, who helped us set up all the lighting. Because of our 2.5D setup, we had to create some custom solutions. But once we got it all up and running, it really elevated the game massively.
Did your artists work directly in Unity?
Yes, everyone was working directly on the project at once, which saved us huge amounts of time. Having an artist or designer implement something directly is so great. This not only saves the programmers time, it also allows the artist or designer to get it looking exactly how they want it to.
Back when we started in Flash, everything had to be implemented into the project by one person, and we’d send assets over email. This created a huge bottleneck. It’s such a relief to be able to put the tools in the hands of talented artists and let them do their thing!
How did you iterate on what are essentially two different game concepts, while maintaining the scope of your project?
It was definitely a challenge. Cult of the Lamb only works when both sides of the game feed into the other – when one side is broken or not as good as it should be, the whole game falls apart. It really didn’t come together until quite soon before the release. We just kept working as hard as we could and dragged the game kicking and screaming over the finish line.
We still have loads of ideas for the game – but it just came to a point where we had to stop adding new stuff and focus on making it as cohesive as possible and the game loop itself as compelling as it could be. That’s where the real magic of the game is. We plan to keep adding more stuff to the game post release.
How did you test features as you added them?
Everyone on the team would do regular playtests. Later in development, our publisher helped us to connect with a focus group who gave us feedback. Ordinarily we would have exhibited the game to get player feedback, but due to COVID, we were essentially making this game alone in the dark. We had no idea what people would think of it!
Thinking about the roguelike elements, how did you implement randomization? What was most difficult to balance here?
Our team has a huge range of skill levels when it comes to gaming. We balanced “easy” to Julian, “medium” to me, and “hard” to Jimp.
The other nice thing about dungeon crawlers is that you don’t really need the randomization to be very balanced. It’s actually more fun when you have a run where you get lucky, and sometimes you get really unlucky. It’s that variety that makes it fun!
Balancing was mostly focused on enemy and boss HP against the level of your character’s starting weapon. Then there was experimentation with faith and hunger levels.
We also have a lot of things under the hood of the game that adjust to the player if you’re struggling. For example, if you’re low on health, you’re much more likely to find a heart in the grass or to loot one from a chest.
During our Twitch stream at GDC, you and the team talked about how taking advantage of the cult members is central to the game. How did you ensure that your players would feel like they were making difficult yet impactful choices when managing the cult?
That was a decision we made very early on, and it pervades the entire DNA of the game. Really, it was part of almost every design decision we made.
One thing that took us a while to figure out was how to make sacrificing a follower feel valuable. You originally just got gold for it, but it never felt valuable enough, so we knew we needed to make it more tempting for a player. That’s why we changed it to an instant level-up. Suddenly we found players were sacrificing their followers all the time!
Another idea that we had from almost the beginning was being able to consume a follower to bring yourself back to life. That was originally a core mechanic of the game, but we decided to bring it in a bit later instead. Making leveled-up followers give more hearts is a great example – the cult members you care about more, and have invested in more, we make more tempting to kill. Basically, anything you care about, we try to make it tempting for you to do something horrible to it.
What are the most important things you learned during the making of Cult of the Lamb that will impact how you approach your next project?
Pick a theme and then create three design pillars; that will be how you fulfill the promise that the theme creates. For example, if it’s a game about cults, then you need a sacrifice ritual – even if you don’t yet know how it will be used mechanically.
Once you have those pillars, absolutely every design decision must directly feed back into them. You might come up with a really cool idea, but if it doesn’t support that pillar, then you have to scrap it or your game will become unfocused.
Start with a concept – it’s X meets Y – don’t just make another metroidvania or Stardew Valley clone. Even if you do decide to make another metroidvania, do something to elevate it so that you’re offering something new and exciting. It will make things much easier to get your foot in the door with publishers, socials, and press. Plus, while it might be more demanding, it’s incredibly rewarding to challenge yourself.
Cult of the Lamb is available now on Nintendo Switch™, PC, PlayStation®4, PlayStation®5, Xbox One, and Xbox Series X/S. Follow @MassiveMonsters on Twitter for updates and visit our Indie Innovation hub for more stories featuring Unity creators making waves in the games industry.
Answers attributed to Jay Armstrong.
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