Kefir: A Unity developer case study
In 2009, Kefir leapt out of the starting gates in Volgograd with a team of five making games for Russian social networks. Taking advantage of new technologies and markets for mobile apps, the studio has grown to 165 people and is best known for its crazy-successful Last Day on Earth (LDOE), a zombie survival title. So far, LDOE has garnered a whopping 83-million downloads, a million daily active users (DAU), and so far, over $125M in gross revenue. Unity powers all their launched games.
Bring the genre to mobile, add multiplayer capability, and expand gameplay
Speed production and optimize performance
27 artists and designers, and 23 software and QA engineers
165+ in St. Petersburg and Volgograd, Russia
HQ: Volgograd, Russia
In a market saturated with survival games, Kefir looked for ways to stand out. They decided to focus on three challenging tasks: bringing the genre to mobile natively, developing multiplayer capability and community, and building a simple UI for relatively complex gameplay.
“We pride ourselves on creating intuitive resources that don’t need to be explained, so we consciously limit the number of buttons, settings and instructions that appear on the screen,” said Petr Kostylev, Kefir’s Art Director. Still, he understands that some players like instructions. “We really hate tutorials,” he joked, but promised that they’ll provide some for those who like them.
So, where does Unity fit in the LDOE world? To start, the studio uses Unity to speed up and optimize their game architecture and coding tasks. Kefir’s artists use it to create and apply humanoid avatars, inverse kinematics, and particle systems. And the business teams use Unity to ensure easier, more effective ways to attract new players and sustain revenue growth through user acquisition (UA) and ad placement strategies. For LDOE, Kefir has embraced a wide range of Unity’s offerings.
- Soft-launched mega-successful LDOE in just 62 days
- Highly focused teams solved different game mechanics by working on separate Unity modules in parallel
- Enhanced monetization and marketing strategies with Unity Ads, Unity IAP, and Audience Pinpointer
- Achieved smooth gameplay experience across all devices using the Unity Memory Profiler
Design it before you build it
Most game reviewers note LDOE’s smooth-running gameplay. To achieve this, Kefir used a variety of techniques, including combining meshes to optimize the number of draw calls and simplifying the UI with a minimum number of atlases.
According to Technical Lead Roman Romanenko, “The most important thing is to focus on creating project architecture at an early stage of development. For example, our basic design patterns solved the inventory system and building mechanics.”
To save more time, Kefir’s developers used a custom “combined sprite” component to draw multiple sprites at once. They also reused objects from fixed pools when possible, minimizing the number of instantiated objects, and enabled automatic user-graphic settings based on device configuration. The Unity Memory Profiler was an important tool that helped them regularly ensure optimal performance across all Android and iOS devices by measuring the impact of all aspects of the game in the device memory.
Nurturing the wider game community
Beyond its games, Kefir has an admirable reputation for openness, freely pointing out competitors’ strengths and commenting on gaming trends in their blogs and at industry events. “Being a true game developer/designer requires understanding, studying, and playing the best games, wherever they come from,” said Kostylev.
He feels this attitude is important for everyone, from startups to established studios. “If you pay attention to your own emotions while you’re playing someone else’s game, you can stimulate a lot of creativity and get a lot of fresh ideas.”
Kostylev also pointed out the importance of not simply emulating game elements that have worked for others. “That leads nowhere – you need to focus on your own individuality. One of the reasons Unity is so valuable for us is because it makes it easier to express ourselves and try new stuff.”
Growing their player base and revenue
In addition to game creation, Kefir uses Unity to monetize their game through ads and in-app purchases (IAP), and to grow their game with UA strategies. While Kefir integrates advertisements into LDOE using Unity Ads, they try to minimally impact their game world by fine-tuning the frequency of impressions, and they especially appreciate how Unity Ads minimizes external calls in Android environments. The bulk of LDOE’s revenue, however, comes from IAP. According to Andrey Kulakov, Kefir’s Head of Marketing, “By design, ads only make up perhaps five percent of our game revenue. Our priority is the game and IAP, and Unity IAP makes that very easy for us.”
A small in-house team is dedicated to UA, focusing mainly on performance marketing. “We recently started running Unity Audience Pinpointer campaigns as part of our UA strategy with Unity Ads. This has helped us meet our return-on-ad-spend (ROAS) goals while also letting us scale campaigns and increase volumes. We’re moving a larger portion of our acquisition budget towards it,” said Kulakov.
However, he added, “Our top positions in the charts are the direct result of the work and excitement we put into our games – which we believe is ultimately the best UA strategy possible.”
Going beyond the Last Day on Earth
Once LDOE became a beloved game with millions of players battling zombies in a nightmare landscape, another Kefir team took the title into a time machine and emerged with Grim Soul: Survival, a dark Middle Ages fantasy replete with castles, dungeons and plenty of impressive medieval weapons and tools.
So, with these huge successes under their collective belt, what does the future hold for Kefir? On the Unity front, Romanenko mentions that the LDOE team is looking forward to using the Scriptable Render Pipeline (SRP) to “have more control over their shader systems. We’ll also start using Cinemachine, the procedural camera system, because I know we’ll get some great effects from that,” Romanenko added. “Unity was key for building and launching Last Day on Earth. And it’s our most successful game to date. As for the future, our new projects will be daring as always!”
Here are some additional insights into how Kefir created the most popular survival game on mobile and soft-launched it in just over two months. To start, the studio chose Unity for Last Day on Earth because it best-suited their agile development environment.
During development, different teams focused on key areas of the game, iterating and polishing aspects like game mechanics, inventory menus and travel maps, readying them until the adaptation to mobile worked well. This well-thought-out strategy focused on ensuring the complex mechanics could be displayed cleanly for the players. Based on the much-loved UI, they succeeded.
“We’ve done a lot of things to tailor Unity for our needs. For example, we’ve combined meshes to optimize the number of draw calls, simplified the UI with a minimum number of atlases, and consolidated sprites (custom components) to draw several at once. As well, we regularly employ the Memory Profiler and we use object pooling when it’s possible. We also set up our content management processes to minimize instantiation. Finally, we configured our user graphics so they are optimized for each device.” – Roman Romanenko, Technical Lead, Kefir
Participating in game tournaments and nurturing the local gaming community are a big part of Kefir’s culture. Because the studio lives and breathes gaming, their enthusiasm and deep experience ultimately translate into ideas for new product features.
Launched in May 2017, the game has 1M daily players, 83-million downloads and has made over $125M. Last Day on Earth has been sitting in the Top-150-grossing game charts on Google Play and the AppStore since its release.
Working on top F2P titles like Last Day on Earth can be stressful. In parallel, Kefir teams are orchestrating live in-game events, engaging with the local community, honing their UA strategies, and preparing the next feature-filled update. To help de-stress staff, they offer activities like theme parties, travel, and professional development.
And just like in some MMO games, Kefir’s 100+ passionate staffers accumulate “dragon kill points” (DKP) when they achieve certain company goals. Supplementing monetary bonuses, DKPs can be spent in auctions on the latest gadgets, cameras, gift cards, trips and more.