Eliminate combatants with, or affected by, your Stasis abilities.
"Spider's got eyes all over this system. What do you wanna bet he has an inside man on Europa?" —The Drifter
You discovered intel that suggests the Stasis weapon is being held in the Fallen city. Drifter's going to find you a way in. In the meantime, practicing with Stasis will be good preparation for learning to use this experimental gun.