turrets attempt to stop Zero's escape. Upon sight of Zero both turrets and guards will attempt to shoot, while scientists will cower and run away. Once spotted by one human they will most likely alert other humans of Zero's presence. Alarms that are activated can be turned off by destroying the alarm coil or moving it off the alarm pad. Sound and sight also play a prominent role in the game. Zero is about half the size of the average human and so is able to hide behind many objects that are scattered across the map without being seen. Sound will also alert the guards to Zero's presence. Footsteps, knocking into objects, and Zero's powers will create sounds audible to the human ears prompting an investigation, though many of these sounds can be made inaudible through upgrades. Upgrades can be purchased at stations throughout the game. Upgrades cost grub energy that has been collected throughout Zero's journey. Grubs are small parasite-like creatures that cling to objects and give off a purple glow. This glow makes them easier to spot, although many of these grubs are located in hard to reach places and require extra skill or more powers to reach. Once a grub is found, Zero consumes it and absorbs its energy. Zero will come across puddles of water early on in the game and discovers that being exposed to small amounts of water will nullify his powers temporarily. This is indicated by Zero having a sudden loss of color and a different walking animation. Unfortunately for Zero, the scientists also discover this weakness. They exploit this weakness by creating a malleable water substance that they primarily use as a shield. Zero can't walk, warp, echo, or use a hologram to get past these shields. When exposed to large quantities of water, Zero will die. The facility is located underwater. Throughout the game, Zero will find remains of other aliens and will be able to absorb their old powers in order to aid his escape. The second power Zero unlocks is a solid hologram, known as Echo. Zero's echo ghost will move independently from him, but Zero is unable to move when this power is activated. All enemies can see Zero's echo but they can't tell it apart from the real Zero. If Zero's echo is killed, it will dissipate. The hologram can pass through all objects and move across