A large variety of pre-built objects are present in levels which may be interacted with. Those, along with objects that have been constructed out of simple shapes can be given specific materials, which act in a manner physically similar to those they represent. Examples include soft sponge, gripping rubber, and tough wood. Objects that are built with mechanical components, such as motors, pistons, jets, wires and springs also act appropriately. Along with these objects, levels contain dangers that the player must avoid. Examples include objects or platforms that have been set on fire and explosives that can damage the player's Sackboy if he strays too close. Explosives can also be used to blow up sections of the level. The player's Sackboy can also be crushed to death if trapped under or between heavy items and drown in water. As the player progresses through the level, they encounter checkpoints - points from which the player can resume upon death.