version of a game on the insert CD-ROM media for gaming magazine, and then later as digital downloads from various sites like Tucows. id Software is credited with successfully implementing the idea for both Wolfenstein 3D and Doom, which was later used by Apogee (now 3D Realms), Epic MegaGames (now Epic Games). Several key genres were established during this period. Wolfenstein 3D and Doom are the formative games of the first-person shooter (FPS); the genre itself had gone by "Doom clones" until about 2000 when FPS became the more popular term. Graphic adventure games rose to prominence during this period; including the forementioned Myst and The 7th Guest, several of LucasArts adventure games including the Monkey Island series. However, the adventure game genre was considered dead by the end of the 1990s due to the rising popularity of the FPS and other action genres. The first immersive sims, games that gave the player more agency and choices through flexible game systems, came along after the rise of FPS games, with games like Ultima Underworld: The Stygian Abyss and Thief: The Dark Project. Thief also expanded the idea of stealth games and created the idea of "first person sneaker" games where combat was less a focus. Real-time strategy games also grew in popularity in 1990s, with seminal games Dune II, Warcraft: Orcs & Humans and Command & Conquer. The first 4X (short for "Explore, Expand, Exploit, Exterminate") strategy games also emerged during this decade, popularized by Sid Meyer's Civilization in 1991. Alone in the Dark in 1992 established many elements of the survival horror genre that were in the console game Resident Evil. Simulation games became popular, including those from Maxis starting with SimCity in 1989, and which culminated with The Sims, which was first released in early 2000. Online connectivity in computer games became increasingly important. Building on the growing popularity of the text-based MUDs of the 1980s, graphical MUDs like Habitat used simple graphical interfaces alongside text to visualize the game experience,. The first massively multiplayer online role-playing games adapted the new 3D graphics approach to create virtual worlds on screen, starting with Meridian 59 in 1996 and popularized by the success of Ultima Online in 1997 and EverQuest and Asheron's Call in 1999. Online connective also became important in genres like FPS and RTS, allowing players to connect to human opponents over phone and Internet connectivity. Some companies