A controversial website and a viral tweet has prompted a fierce debate in Runeterra's community this week about what is and isn't a fair use of players' decklists.

A Primer on Riot's Developer Resources

Some quick background is necessary before diving in to this week's controversy. Riot provides powerful developer resources for most of their games, including Legends of Runeterra. These are intended to allow 3rd parties to design features for enhancing players' experiences like plugins that tell you when the next dragon will be up in League of Legends or what your current chances of rolling a particular unit in Teamfight Tactics are. For LoR, Riot provides a few things:

  • A database for all the released cards and their associated artwork.
  • A C# library for converting deck lists to deck codes or vice versa.
  • An API for live information queries like masters rankings, win/loss data for a particular game, and deck codes for particular players.

Many of the services you use on Out of Cards benefit from these resources, and it cannot be understated how great it is to have them available and well-documented. Our card database is resynchronized with theirs, the card art you see on our webpages is uploaded from their database, and we use their library to make sure players can both create new decks from a deck code and import decks from Out of Cards into their local clients. We even have an internal staff-only resource that polls top players' recent history to help us research and create articles like this week's "13 of the Best Performing Ranked Decks in Legend of Runeterra". Why is this resource staff-only and not public, you ask? Well, we want to ensure that none of our queries are used in a manner that is inconsistent with Riot's terms of use. You see, you need to agree to Riot's policies before they will grant you permission to make API queries, and they are very particular about how the information from these queries should be used (emphasis ours). 

Quote From Riot Policies (General)

Game Integrity

  • Products cannot alter the goal of the game (i.e. Destroy the Nexus)
  • Products cannot create an unfair advantage for players, like a cheating program or giving some players an advantage that others would not otherwise have
  • Products should increase, and not decrease the diversity of game decisions (builds, compositions, characters, decks)
  • Products should not remove game decisions, but may highlight decisions that are important and give multiple choices to help players make good decisions
  • Products cannot create alternatives for official skill ranking systems such as the ranked ladder. Prohibited alternatives include MMR or ELO calculators

Since it's ambiguous what exactly "unfair advantage" means relative to LoR, David 'Tuxedo' Chow, Senior Developer Relations, elaborated in a blog post the same day they made the match history API publicly available (emphasis again ours).

Quote From David 'Tuxedo' Chow

Creating an uneven playing field

In Legends of Runeterra this is a little different than in our other games and with that in mind there’s one area in particular we’d like to focus on; scouting. Scouting in a game like Legends of Runeterra creates a strong advantage for a player. It’s important that both players play the game on a level playing field and while tips on how to play against a deck archetype is okay, providing privileged information about a player by sifting through their match history isn’t.

So What Happened?

As you probably guessed, one developer ran afoul of Riot's intended usage. Specifically: in addition to providing leaderboards, meta lists, and personal win/loss rates, the website runeterra.ar added a feature where they would query your current opponent's deck code and then show you the corresponding deck list on their webpage. No more guessing whether or not your opponent ran cards like Atrocity or The Ruination: you could see exactly how many copies were in their deck and adjust your game plan accordingly. 

Runeterra.ar flew largely under the radar until Wednesday evening, when streamer eMOEtional posted a tweet emphasizing how much easier playing ladder was when using this feature. This tweet quickly went viral amongst the LoR community, and when the LoR dev team took notice, they took immediate action.

Quote From RiotUmbrage

We shut it down [= disabled their API permission] for now. Our guardrail with 3rd party devs is no competitive advantages. The spirit of this is: convenience is fine (track my deck) and meta pictures (prep for tourney), but not in the moment for a particular match. We'll continue to iterate on this with y'all!

…We didn't shut down [runeterra.ar's website]; we turned off their access to the API so the data won't be updated and reached out to the devs to figure out how to proceed. Totally agree there are many uses that should continue to be supported.

runeterra.ar has since removed the decklist feature from their website, and their API access was restored less than 24 hours after it was revoked.

The Community Debates

After the deck-viewing feature became widely known, many players expressed shock and outrage. Several called it outright cheating; some compared it to the practice of stream sniping. Others speculated that if this practice became prominent, it would stifle the "surprise" element that off-meta decks and homebrews rely on to compete and decrease meta diversity in the long run.

Some players were sympathetic, however, and pointed out similarities between what runeterra.ar was doing and -- at least on the Masters level -- what is possible by using the in-client Leaderboard. As an example: in DucklingLor's stream this week, he lost a ranked game playing Diana + Nocturne Nightfall against 虎牙Ace's Zoe + Sol deck. After the loss, he went to the Leaderboard, imported Ace's deck into his library, and memorized what combat tricks and health gain that deck had. "It's a good thing to do if you keep running into the same people, by the way," Duckling commented. Certainly, this approach is much more commendable than simply browsing the information during the match for every opponent, but on a practical level, the differences between the two are debatable.

A few players even argued that the game would actually be better it if decklists for both players during ladder matches since that is more representative of the closed decklist format of seasonal tournaments.

How do you feel about this debate? Share your feelings with us below!