It attracts up to twelve small objects and Fauna to itself. Its main uses are to ensnare fast-moving fish, like the Peeper, for the Player to catch more easily and to collect materials broken free with the Prawn Suit Drill Arm.
The Gravsphere can be placed in an environment with an abundance of fish to act as a fish farm, although a Alien Containment tank is more reliable.
The Gravsphere takes up 2x2 item slots in the player's Inventory. Although it requires a Battery to be built, it does not use energy. The Gravsphere attracts fish and any small item that can be picked up manually within reach. Plant material, such as Creepvine Seed Clusters, are the exception. It is best to place it on the ocean floor. It should not be placed in open water due to a bug in which schools of fish will cause the Gravsphere to be towed away by the school.
It is suggested to remove the objects caught by the Gravsphere before picking up the sphere. If the player is in the open ocean, currents may send the objects 30 meters or more away if the player picks up the Gravsphere with objects still attached it.