Focused on the original trilogy of the Star Wars universe, LEGO Star Wars II: The Original Trilogy brings some innovations over the first title, making it more similar to its PC and console counterpart than the previous game. During the story mode, the player is joined on-screen by two other characters, and can change between them to use their specific skills to proceed. Characters share a life bar of four hearts, with the rate of depletion changing according to each character (a stormtrooper will lose three hearts when hit by a blaster, Vader will take two or three hits before losing one). If a support character is "dismantled" by attacks, there's no problem, but letting that happen to the controlled character means a loss of stud points and a drop on the "Super Kit" gauge.
Gameplay has been changed to accommodate the lack of lightsaber battles in the later episodes, and so blasters are a lot more effective and fire faster, but have lost their "charge" mode. New flight missions are also included, which allow the player to attack both Death Stars, skim the surface of the forest moon of Endor in a Speeder, escape from an asteroid field with the Millennium Falcon , or draw wires around the legs of Imperial walkers in Hoth. There are three major character classes: droids (unable to fight), Jedi (melee fighters capable of interacting with larger objects to uncover hidden studs and with different Jedi powers) and Blaster users, which can fire at an enemy from a distance, as well as assemble smaller objects. Gameplay remains a light jump-and-slash isometric game, with the goal being usually to go from point A to B, while pulling levers somewhere in the level.
Gameplay cannot be entirely completed without playing in Free Mode, as many doors can only be opened or even reached by using the unique special abilities of one of the 36 unlockable characters. To acquire characters for Free Play, the player now needs to accomplish three things: earn enough credits, complete a level, and get all "mini kits". Characters that can be unlocked include enemies and heroic characters like Yoda.
There are also additional items to be bought, including music, palette swaps, new game modes, lightsaber colours and hints.