Off-the-shelf, it costs a maximum of 35 credits (the first handful of Engineers you receive will easily drop it to the mid-low 20s), and holds a charge for two stun attempts, but even then only if the target has 4 or fewer health remaining (49/70/80/90% on 4/3/2/1hp). Not also is it needed to move the story along, but the weapon drops from captures, and the results from interrogations will vastly expand the potency of XCOM. The Arc Thrower will be one of your first plot-centric fabrications and like the various stun devices in previous iterations of XCOM, it may actually be the most important weapon in your arsenal against the alien invaders. ' I trust you have tested this thing.' - Shaojie Zhang