LEGO Indiana Jones 2: The Adventure continues the players' journey through the Indiana Jones universe with "LEGO-fied" characters. This time, the main part of the game focuses on the events of Indiana Jones and the Kingdom of the Crystal Skull , with three campaigns retelling the story in a humorous, light-hearted way similar to the other games from the LEGO series . The other three campaigns turn their focus on the original three films but with different scenes and levels that can't be found in the first game.
The game is a third-person platform/action game where players take control over various heroes, including Indiana Jones and side-characters. Each character has unique abilities, fears, and weapons. For example, Indiana Jones has his whip to pull items out of reach or constrain enemies with, while his son Mutt is a skilled repairman. The characters also have phobias (snakes, rats, spiders), each corresponding to their personalities.
Instead of a central hub, the game's story and locations move forward simultaneously. The game starts at the University campus, which becomes the main hub, but eventually shifts to the dig-site in South America. After completing missions, new parts of the hub are unlocked through unlocking new characters or vehicles, allowing access to previously unreachable territory. Vehicles can be unlocked by finding them in the hub and paying studs, which are collected by destroying scenery objects, building stuff, and so on.
The game features an editor to create unique heroes from parts, as well as a level editor where players can spawn items and place them with their character. The two-player co-op mode returns, allowing two players to play through the whole game. The second player can enter the game at any time by pressing a button on the second controller, and they are no longer restricted to the same area.
The game's levels hold many secrets that require different characters to unlock them, requiring multiple playthroughs to find all bonus items and complete the game 100%. The game also features a high amount of replay value due to its large size and available vehicles and secret locations.