What is EOMM, Engagement Optimized Matchmaking?

Competitive multiplayer games often employ skill-based matchmaking (SBMM) algorithms in order to match players of similar aptitude in the same lobbies. This method of arrangement has a  controversial counterpart, “engagement optimized” matchmaking. This kind of matchmaking, believed to be used and partly patented by Activision and EA, prioritizes player retention and in-game purchases.

Most information regarding how EOMM works is theoretical and based on personal experience. For example, some investigative gamers allege that a cycle exists and resets periodically, beginning with one’s first game of the day being matched against lesser-skilled players. A dominant win to begin your session thus encourages you to keep playing.

Other theories contend players who purchase in-game content will be paired with better players, as a subtle reward for buying items and reinforcing incentive to continue doing so.

Of course, understanding EOMM also requires the context of SBMM. While ranked modes in first-person shooters are often thought of as the primary match-made experiences, casual public lobbies often also utilize this skill-based matchmaking.

Though it’s arguably preferred between the two systems by casual communities, there are complaints to be had about SBMM. If you’re deemed highly skilled based on your recent in-game performance, for instance, you will only be matched against tough opponents. For some content creators, this also means no “pub-stomping” (when an experienced and well-organized team obliterates the less experienced and less organized members of a lobby).

While SBMM is widely known about, EOMM is nearly a conspiracy. In a way, however, SBMM is a more transparent form of EOMM, aiming to keep up engagement by challenging players without exhausting them.