Strato-Sentinels are used for mining and building for the Forerunners. In the case of mining, they will be found under the command of a Minor Miner. In the case of building, they will be found under the command of a Minor Builder. Strato-Sentinels are armed with several miniature Mining Lasers, and one very large Mining Laser. Both can be used for offense and defense if the Forerunner building/mining side falls under attack.
Forerunner Army 