Players create a character as their avatar in the game's medieval-style virtual world. Humans, Elves and Dark Elves start off in the Kingdom of Aden while Dwarves and Orcs start off in the Kingdom of Elmore (Elmore was an entirely different continent until recent versions of the game that have since joined Elmore to Aden). Players can choose from either fighter or mystic professions at the start, except for Dwarves which are only able to select the fighter profession. This choice acts as an archetype for later profession options. Each race has its own set of classes, even if humans, elves and darkelves have a lot of classes which are very similar to their counterparts in the other two races.

Players have a variety of things they can do for fun in the game. They play alone or as part of a group to fight monsters and complete quests for new skills, experience points, and items. Player versus player (PvP) is a significant portion of the game. The game provides many social, political, and economic aspects which are developed through the community and by the actions, in-game, of single players. Lineage II features siege warfare like the original. To make sure PvP stays under control, the design includes a Karma system that provides negative consequences for killing other players when they are not fighting back.

Lineage II features greatly improved third-person 3D graphics over its predecessor. The game uses the Unreal 2.0 Engine developed by Epic Games.