Xel'Naga

Blizzard Entertainment's real-time strategy game series StarCraft revolves around interstellar affairs in a distant sector of the galaxy, with three species and multiple factions all vying for supremacy in the sector. The playable species of StarCraft include the Terrans, humans exiled from Earth who excel at adapting to any situation; the Zerg, a race of insectoids obsessed with assimilating other races in pursuit of genetic perfection; and the Protoss, a humanoid species with advanced technology and psionic abilities, attempting to preserve their civilization and strict philosophical way of living from the Zerg. Each of these races has a single campaign in each StarCraft real-time strategy game. In addition to these three, various non-playable races have also been part of the lore of the StarCraft series; the most notable of these is the Xel'Naga, a race which features prominently in the fictional histories of the Protoss and Zerg races.

The original game has sold over 10 million copies internationally, and remains one of the most popular games in the world. One of the main factors responsible for StarCraft's positive reception is the attention paid to the three unique playable races, for each of which Blizzard developed completely different characteristics, graphics, backstories and styles of gameplay, while keeping them balanced in performance against each other. Previous to this, most real-time strategy games consisted of factions and races with the same basic play styles and units with only superficial differences. The use of unique sides in StarCraft has been credited with popularizing the concept within the real-time strategy genre. Contemporary reviews of the game have mostly praised the attention to the gameplay balance between the species, as well as the fictional stories built up around them.

Across the course of the game's development, the races and graphics of StarCraft have changed drastically from Chris Metzen's original concept art. In particular, since their initial public debut at E3 1996, the Zerg have seen extensive changes to their visual design. This was primarily due to Blizzard's attempt to steer the game away from the visual appearance, unveiled at the 1996 E3, that had earned the game a derisive label of "Warcraft in space". The Zerg were originally known as the "nightmarish invaders", later becoming the "Zurg", and then renamed again to its current spelling to avoid any potential trademark conflicts with Pixar's Toy Story character of Emperor Zurg. In the early alpha versions built by Bob Fitch, the Zerg still showed their insect-inspired base, but their appearance was heavily dominated by spikes and bright shades of blue and purple. Early Protoss concept art showed a green and blue color scheme in their mechanical armor. Closely hewing to the familiar visual style of Warcraft II: Tides of Darkness, the build received much criticism from industry press, prompting a redesign of the game engine and an overhaul of the races' respective visual designs.

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Wikipedia