In Hidden Deep, players explore an underground cave system deep below the ocean. They are tasked with discovering what happened to a missing scientific team and controlling a second team. Alongside numerous weapons vehicles, players have multiple gadgets they can use. This includes the Terra Scanner.
The Terra Scanner is one tool at the player’s disposal that will be crucial when proceeding through the cave system. To use the Terra Scanner, press N on the keyboard. Your first chance to use this will be on the mission called Lost.
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The Terra Scanner is used to identify empty chambers below the player. This is necessary to find hidden entries and pathways. Once the player has used the Terra Scanner on the ground, they will need to use explosives to clear the opening.
Be mindful that it is possible to fall to your death when opening passages, so use your grapple. You should also get far enough away from the explosive before it detonates, or you will also die.
For more information on Hidden Deep, check out How to use the grappling hook in Hidden Deep and All achievements in Hidden Deep on Pro Game Guides.