Stud Collector
You will earn Lego studs in many different ways in the game. Some you get from breaking objects while others are lying around or found in hard-to-reach places. Punch everything in sight. Most objects made out of Lego blocks will crumble into studs. Once you earn enough studs in a level you will reach "True Adventurer" status. Obtaining this rank will help you unlock bonus missions and other features.
Visual Cues
If you get stuck during a level, look closely for visual cues. Often the in-game camera will focus on a certain area, such as a monkey on top of a wall holding a key you need. Other times items will sparkle to indicate you should use them in some capacity. Platforms which you can use your whip to swing to may be lighted, or a spot where one of your characters should jump is shining.
Treasure Hunter
Each level has ten treasures. Some are hidden, while others are in plain sight, but you must figure out how to reach them. Collect all ten in a stage to build an artifact. In addition to earning 50,000 bonus studs, you will get new bonus levels by building these artifacts. Use a cheat to help your search if needed. Enter the code "VIKED7" on the math classroom blackboard at Barnett College to get the treasure detector.
Unlock Characters
Use the Barnett College math classroom to input codes that will unlock many secret characters in the game. The following are the cheats to enter to unlock the given character: "VJ3TT3" for Captain Katanga, "2K9RKS" for Colonel Dietrich, "8EAL4H" for Colonel Vogel, "3NFTU8" for Donovan, "JSNRT9" for Dr. Schneider in her desert outfit, "VMJ5US" for Dr. Schneider in her officer's uniform, "H0V1SS" for a Hovitos tribesman, "VJ85OS" for Indiana Jones in an officer's uniform, "2NK479" for Laoche, "NFK5N2" for Maharaja, "VN28RH" for a Pankot guard and "MEN4IP" for Willie Scott in pajamas.