It’s that time of the year again; the API Challenge is once more upon us! This time we are giving participants a full month to work on their projects and cannot wait to see what you come up with.


One Prompt; Multiple Categories


This challenge we’re narrowing down the prompt and providing multiple categories to provide a clear focus while also clarifying how your submission will be judged.


Submit a project that utilizes the League Client API’s and falls in one of the following categories.


  1. Entertainment

  2. Usability/Practicality

  3. Creativity/Originality

League Client API’s

We announced a little while ago that we are now allowing applications that use the League Client API’s. If you want to know more about them you can go here. For this challenge we want people to use the following endpoints, using any others will result in disqualification.


LCU endpoints

Additionally you may use current-summoner under lol-summoner to get information about what summoner is logged in.

Let’s take a second to dive a little further into each category. The category you select will be the primary basis for which you submission will be judged along with the rest of the judging criteria.



We don’t want to be too restrictive so this category is primarily focused around creating an entertaining experience. Hint: Social experiences that allow you to involve friends or share your experiences are a big plus.



Many of the winning submissions in the past have fallen within this category leaving other types of the submissions in their wake. We want to ensure that developers aren’t forced to create something useful/practical which is why we’ve created a category specifically for these kind of submissions. We’ll be looking for submissions that will provide a tangible benefit to the entire community and will hopefully continue to provide value to players even after the contest ends.



Creative and original ideas are always a breath of fresh air. Developers often build and iterate on successful ideas, but this category is meant to reward the individuals who aren’t afraid to challenge convention in pursuit of new and revolutionary ideas. We are always looking for ways to encourage developers to think outside of the box.




All entries will be required to provide a public GitHub repo link as part of their submission. You should include sufficient documentation with a demo if at all possible. We’ll be using the following criteria to determine the winners of the challenge:

  • Technical difficulty

  • Clarity/Presentation

  • Project documentation

  • General polish


I can’t stress enough how important it is to have both good documentation and a presentation for your entry. When it comes to documentation, it doesn’t matter if you discovered time travel, if no one can replicate your project it loses value. As for having a presentation, you’ve spent three weeks working on your “baby” and everyone else takes around 3 minutes to judge it. Spend a couple of minutes highlighting what makes your project special and why other people should care. You can’t assume everyone will know exactly what you did and how it’s amazing.


Over the last API Challenges, we’ve noticed many projects that have accomplished some impressive feats. They’ve run into unique challenges and have found elegant solutions to overcome them, however it’s fairly common that the challenges developers encounter aren’t highlighted as part of their presentation. One of the goals for each API Challenge is to strengthen and empower the developer community as a whole. When you document your project, spend some time talking about the technologies you used, why you chose them, and lessons you learned when working on your submission. Even an incomplete project can offer valuable insight to developers that follow in your footsteps.




There are some rules that are unique to this competition, so please read the following carefully along with the general rules below.

  • Your project should not offer itself as an alternative source of data apart from the Riot Games API (e.g., please don’t create a database of info with the intention of redistribution).

  • Developers participating in this contest will have to register on the Riot Games Developer Portal. You can register for free here.

  • Each team member must have have a valid League of Legends Summoner Name (they must login to the client at least once).

  • A temporary production API key may be granted in order to aid in the development of a submission. If you’d like to be considered for a temporary production API key, please let us know on the developer Discord. You’ll be required to provide a full description of your concept prior to being considered for a temporary production API key.

  • Potential winners will be contacted via the email associated with the submitter’s League of Legends account. Please update the email associated with your League of Legends account before submitting your entry, and watch it closely after the contest deadline.

  •  Please ask your questions here, in the Riot Games API Challenge 2018 channel in Discord.


General Rules

  • The work submitted to this contest must be in English.

  • The contest starts December 21st, 2018 at 12:01 AM Pacific Time (PT).

  • The deadline for all entries is January 23rd, 2019 at 11:59 PM Pacific Time (PT).

  • Winners will be announced and posted on the Riot Games Developer Blog on or before February 4th, 2019 at 2:00 PM Pacific Time (PT).

  • Teams are to be no larger than two individuals.

  • The full official rules can be found here.

  • The work submitted to this contest must be originally made for this contest. You may utilize any free resource that was made publicly available prior to the start of this contest.

  • Riot Games is the sole judge of the contest. All judgments are final.

  • When you’re ready to submit your work, head over here.

  • Unfortunately, residents from the following regions are ineligible to enter due to legal or logistical issues: Iran, North Korea, Iraq, Sudan, Syria, Cuba, Greece, Brazil, South Korea, Japan, Italy, and Quebec.

  • Please note: Current partners, contractors, and employees of Riot Games are not eligible for participation in this contest.




Like the last API Challenge, we’ll be issuing prizes to a winner in each category and three runners-up split amongst all categories. We don’t want prizing to be the primary incentive for participation, but we do want to reward the efforts of the participants. The prizes for each team member (maximum of two (2) members per team) are listed below:


First Place

  • Each Member will receive 50,000 Riot Points (RP)

  • Work highlighted on certain Riot Games and League of Legends web pages



  • Each Member will receive 15,000 Riot Points (RP)

  • Work highlighted on certain Riot Games and League of Legends web pages