EverQuest: The Shadows of Luclin (also called SoL, or Luclin) is the third expansion released for EverQuest, a massively multiplayer online role-playing game (MMORPG). The expansion focuses on high-level content, providing a number of zones meant to be used by large groups of players and many extremely powerful monsters to fight.
The expansion takes place on a moon of Norrath called Luclin and introduced the Vah Shir, a catlike playable race, and the Beastlord character class. Notable NPC races that were added to the EverQuest universe are the Shissar, a snake-like race, and the Akhevans. The Shadows of Luclin also incorporates a new game engine, new character models, and gave players the ability to design graphical user interfaces. The player characters' appearance was completely redesigned giving them more layers and rounder shapes. Mounts were also introduced with this expansion, they allowed players to regenerate their Health and Mana as if they were sitting without generating as much aggro (hatred from monsters). Alternate Advancement started with the Luclin expansion, allowing players to further grow and customize their classes.
It includes many zones in which players of all levels can experience, several raid encounters such as the Lord Inquisitor Seru and a high-end raiding zone, Vex Thal. SoL also introduced some new events that made encounters more challenging than before, especially in the Ssraeshza Temple zone.
The Shissars, serpent like creatures, were extremely powerful beings and once roamed on the continent of Kunark where they had enslaved the Iksars. Rile, an Iksar hero, brought a revolution and called upon a mystical force referred to as the Greenmist, which killed the Shissars. Fleeing Norrath because the atmosphere became toxic, the surviving Shissars were helped by the Combine Empire and were sent to Luclin and the underwater sanctuary introduced years later with "The Buried Sea".
On Luclin, the Shissars built the temple of Ssraeshza home of the powerful Emperor Ssraeshza (powerful enough to slay gods according to the lore). To protect themselves from the Greenmist, they magically sealed the Grey, a place where no atmosphere exists, and built their temple. Ssraeshza Temple (also known as Ssra) is part of the access to the high end zone of Vex Thal. Defeating the Emperor was necessary and required equipping every player with a key done within the temple and gearing melee characters with special weapons, since the Emperor is immune to regular weapons. Such weapons were introduced with SoL and a referred to as Bane Weapons. Later on, a Shadow Knight only quested weapon was introduced in Cabilis and called the Greenmist (Sacred Khukri of Rile), the most powerful Shissar-bane weapon.
Under the seas they built Zhisza a new sanctuary.
Source: Wikipedia, "EverQuest: The Shadows of Luclin", available under the CC-BY-SA License.