Today, massively multiplayer online gaming is pretty commonplace, with such games covering a huge variety of genres across consoles and computer gaming. Though it wasn’t the first, the game that helped popularize the gaming concept in a hugely successful way celebrates its 20th anniversary this month: EverQuest.

The game entered development at 989 Studios in the mid-1990s before releasing in March 1999, and was published by Sony Online Entertainment. It’s largely considered an evolution of the MUD (Multi-User Dungeon) genre that had existed primarily in text-based format before then; the game’s creators all credited various MUDs, such as Sojourn, as inspirations for EverQuest.

In EverQuest, players create a character based on one of several fantasy races (such as elves, dwarves, gnomes, ogres, and even beast-people that looked like cats, frogs, dragons, and lizards) and then picking an occupation or class. The game allows players to interact with one another and to go on quests together, essentially creating their own stories within the world provided.

EverQuest proved to be a success upon release, with the number of subscribers rising significantly until finally plateauing in 2001. The game quickly surpassed the numbers of its main competitor, Ultima Online. Expansions were released in traditional physical format on a yearly basis after the game’s initial launch, though this was eventually switched to digital distribution.

The game eventually saw a true sequel, EverQuest II, though the number of subscribers eventually began to decline following the release of World of Warcraft by Blizzard, which eventually overtook the entire MMO genre and remains one of the most popular today. However, the original EverQuest has enjoyed continued support and expansions, with the most recent, The Burning Lands, releasing at the end of 2018.