Obstacles include crates which can be used to create platforms to reach higher ledges, fires that must be extinguished before they can be passed, water hazards which only Mr. ESC can swim in, one-way doors, fallen rock walls, exposed electrical wires, and more. Some tools can be used to remove the obstacle (such as a fire extinguisher to dose a fire or a pick-axe to clear rubble). There are some levels that are dark, and a flashlight is needed to see even part of an area of the level.