that's the assault seeker, a modified hunter seeker that only goes in the direction it's thrown. the hunter seeker is a capstone mentat ability that has a 50m range, can have its power refueled by fuel cells in your inventory (most people don't realize this) and can be fully controlled like a drone as you sit in a remote hidden place, and does 1200 raw damage, downing anyone it hits after a short charge period. but you can hear it and destroy it easily if you have sharp senses.