Hi there! I’m Jules Glegg, a Software Architect at Riot, and I’m one of the engineers who helped create Legends of Runeterra. LoR is a strategy card game set in the League of Legends universe - and it’s our first fully realized standalone game since League of Legends came out just over a decade ago!

A whole new game means a whole heap o’ new technology. While we won’t be able to cover all of it in one go, I’d love to give you a glimpse at how we add features to LoR. I’ll describe our process of making it work so we can playtest it, move on to making it presentable using our suite of artist tools, tweaking it for balance, and finally making it shine by adding motion and sound before sending it out to players.

First up, some quick facts about LoR:

It’s created in Unity.

It runs on Windows PC, Android, and iOS.

Almost all code - both client and server - is written in C# . C# is a statically-typed language that prioritizes correctness and legibility . Designers are able to use Python to create scripted content such as cards and quests.

We use Git and LFS for version control. LFS is important because games contain huge piles of binary data for textures, audio, vendor tools, and so on.

On the Shoulders of Giants

Just like its big sister League, LoR is set up to ship a patch every two weeks. This means it’s super important for us to keep the game’s main development branch stable, and to ensure that any high-voltage experiments with new features or gameplay take place in their own development branches.

Let me tell you - there are benefits to being the second game out the door. Our friends in the Riot Platform Group have invested enormous effort into making sure all our “Research and Development” titles can take advantage of the infrastructure that already distributes League of Legends to players around the world. Our team gets a lot of stuff for free, including the new launcher which provides us with ultra-efficient patching, push notifications, and more - all based on the League Client architecture.

This strong foundation allows the LoR team to work in ways that simply aren’t available to a lot of teams. We even use the launcher internally for playtesting! Ours just looks a little more... chaotic: