It’s Endgame Moves Week for Overwatch, wrapping up the cross-franchise educational content series that previously featured Opening Moves Week and Midgame Moves Week. This time we’re focusing on the all-important final stages of each map or match that often mean the difference between victory and defeat. Kicking off the week is a discussion of everyone’s favorite meme: the C9.

If you’ve watched the Overwatch League or even played ranked in the last year, you’ll undoubtedly have seen people spamming “C9” in chat at some point. To outsiders, this might seem like a cryptic code, but it’s actually one of the most popular memes in Overwatch history, with an interesting history that all Overwatch fans and players should know about.

A true “C9” is when a team ignores the objective, running away to take a fight and grab some kills, and ends up losing the round because of their negligence. More generally, it tends to be applied any time a team forgets to stay on the objective—whether that’s a control point or a payload—and loses a round or map as a result.

You’ve surely experienced it in your own games: it’s overtime and stepping away from the objective will result in a loss, but your teammates are desperate for those juicy eliminations to bolster their gold medals. Instead of staying on the objective, the players run away to destroy a stray Lúcio and—tragedy!—the overtime wick burns away, leaving you one kill up and one round down.

It’s happened to us all, even the professional players. The match that launched this meme was a showdown in APEX Season 2 between Afreeca Freecs Blue and—you guessed it—Cloud9. In February 2017, Cloud9 was an entirely different group of players than the London Spitfire roster now run by C9 owner Jack Etienne. Nevertheless, the meme has so thoroughly resonated with the Overwatch audience that it seems there will never be another name for this kind of oversight.

As you can see in the clips above, Cloud9 stepped off the objective three times over the course of a match. Each example was a winnable fight for them, with the third occasion being the most egregious.

If these situations happen to you in ranked, here’s how you can avoid a C9. In the first clip, Cloud9 engaged too aggressively and ran past the objective, not remembering to contest it at all; make sure one player touches the objective within the last three seconds to trigger overtime, and try to deal with players on the objective first! In the second clip, Cloud9 sent one player to flank; if you notice that you’re the only player on your team able to get on the point, remember to prioritize the objective over the eliminations! In the third clip, a D.Va Self-Destruct forced everybody away from the point; if there is no cover on the objective and everyone has to either leave or die, use voice communications to pick a single player to die on the objective and keep it contested!

Perhaps C9s happen more frequently with higher-level teams than in ranked, as professional players are focusing on so many different things at once. One slip in communication can result in all the players assuming somebody else is on payload duty, and within an instant a highly coordinated professional team has committed a C9 and looks foolish on the main stage.

The important thing to remember when you’re spamming “C9” relentlessly in Twitch chat is that this can easily happen in your ranked games too! Overwatch is an objective-based game, and getting eliminations is fun and all—but don’t pull a C9.

Josh “Sideshow” Wilkinson is an analyst for the Overwatch League. Follow him on Twitter and YouTube!