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Clash Royale — Jun 21, 2022

Creator Spotlight: RoyaleAPI!

  • Hey SML!

    Can you introduce yourself to the players? When did you start playing Clash Royale?

Hello, my name is See-ming Lee, but most people know me by my initials SML. I am the founder of RoyaleAPI.

In my professional life, I am a User Experience (UX) Designer and Technologist. I have spent more than 25 years working at the intersection of art and technology in interactive media. I graduated from Yale in 1999, which gives you a clue about how old I am, not that age matters, of course. I currently reside in Hong Kong but have spent 17 years living in the US. I first picked up Clash Royale in 2016 while vacationing in Scotland, and the rest is history…

  • What is RoyaleAPI?

RoyaleAPI is a website that we have built to help players in countless ways, as well as enhance their Clash Royale experience. We have a variety of tools that are available to help everybody playing the game, from beginners to world-class professionals.

New players generally use the simpler features like seeing their upcoming chests.

Intermediate players and CR veterans tend to explore deeper, using more advanced features like our Clan War tools, or keeping up to speed with coverage of game updates.

The professionals trust our esports database to log all the relevant achievements in their careers. Further to this, we have established ourselves as the top destination used in the competitive scene, and our services are essential for any professional players or analysts looking to succeed at any level, from semi-pro to the million-dollar Clash Royale League.

  • What would you say is the main purpose of RoyaleAPI?

I see RoyaleAPI as the Swiss Army Knife of Clash Royale. Our aim is to provide any player, casual or pro, with the tools they need to play, learn and excel at the game. We specialize in finding great decks, perhaps the most critical aspect of Clash Royale. Our comprehensive range covers deck needs for Ladder as well as the variety of decks required to make special challenges as easy as possible.

As with most card games, having a good deck is the basis for a winning strategy, and we can proudly say that many players trust RoyaleAPI to find it.

  • How did it start?

Officially, the founding date of RoyaleAPI is July 28, 2017 — this is the date when the first line of code was checked into our git repo. We are approaching our 5-year anniversary!

In the summer of 2017, we released a public API tool that enabled anyone to develop custom applications for the game. The largest project which came from the initial API was our flagship website: — a proof-of-concept for data analysis. The website served as a means to encourage new projects and to demonstrate the capability of our API. Over time we’ve developed an unmatched database of analytical data to support the casual and competitive community.

Eventually, Supercell released an official API, and although this made our API service redundant, our site was still useful to many players. We realized we could keep working on it to create features that no one else was capable of developing, and we’ve kept doing that ever since.

  • How many people are working on RoyaleAPI?

Our team is made up of two core members and a huge roster of volunteers. I am the only person who works full-time on the project. Alpe123 (Alvaro Peña), our Director of Esports, spends about 20 hours per week on the site. Other members of the core team participate in important discussions and brainstorming sessions. We also work with several data scientists on data-intensive projects, and a huge team of translators who help put our site into 14 different languages.

  • What’s your favorite feature or part of RoyaleAPI?

I am most proud of the monthly balance changes infographic which I first started creating for the entire community a few years ago. Prior to us starting the trend of a single image summary, many creators had demonstrated balance changes using before/after animation. While those videos are useful on the micro-level, I find that the macro view is often missing. The popularity of this single image can be seen by the thousands of upvotes it receives on social media, as well as a plethora of shares.

I have also commenced making short videos each month about the upcoming seasons. Although videos are not traditionally part of our main content channels, I have worked my passion for animation into the mix to create a condensed video, usually under two minutes, to give a bird’s eye view of the upcoming season.

In terms of functional features in RoyaleAPI, I’m most proud of being able to create several unique features which nobody else provides:

  • Real-time deck search with an exhaustive list of options, card filters, and game modes.

  • Matchup - a tool that shows the likelihood of a deck to succeed against other decks.

  • Replay - a timeline view of the game which shows detailed statistics about the game and gives a post-game analysis.

  • Any cool or fun facts that you can share?

I can often tell if a pro player is playing in an important esports event without knowing about it in advance.

When that happens, real-time page views of their battle logs will always spike. It’s also easy to see when a special deck challenge is happening because so many people will search decks for those events. For example, most recently I was alerted of an “anomaly” where deck searches for “The Floor is Healing” were 332,540% more than predicted. As most people have learned, I’m a bit of a nerd, so this kind of data is my idea of fun…

  • What’s your favorite moment in CR history?

When Clash Royale switched to simplified levels.

Looking back, it must have been challenging for newcomers to grasp the concept of 9/7/4/1. If you look at old videos of Clash Royale, I’m still surprised how we managed to understand that max levels were: 13 common, 11 rare, 8 epic, 5 legendary. It seems second nature now, but it was quite frankly demanding on the brain. Well, my brain anyway, so I really appreciated that change.

  • Can you share/tease any new features you are working on?

There are a couple of high-level features that we are working on right now, which we hope to release soon.

Duel search - This is somewhat challenging because the duel set combinations are not easily composed, and we have decided that it likely won’t give any meaningful results if we grab 4 actual decks that people use — the probability of players using the exact 4 decks for war is so low that it would not be statistically meaningful. Rather, we are using some fairly advanced methodology to compose duel sets based on decks’ win rates and use rates. Doing this allows us to find high-performing decks without anyone actually having played the exact set before.

Badge Leaderboard - In addition to the in-game badges, we have implemented many custom badges for players. Noting that players are extra motivated by ranks and bragging rights, we plan to turn most of these custom achievements into full leaderboards.

  • What is your creator code?

Our creator code is RoyaleAPI — btw, you can type all the letters in lower case if you like!

You can support RoyaleAPI by using the code RoyaleAPI in the shop, and by following them on:

And of course, the RoyaleAPI website.