From Destinypedia, the Destiny wiki
Much like its minor counterparts, the Overload Captain will keep its distance from there, while raining down their heavy weaponry upon their assailants. These Captains have their standard teleportation ability, but will utilize this ability once they are either being assailed or pressed by their attackers, and, thanks to their ability regeneration, will instantly regain their teleportation ability.
To prevent this ability and allow the players time to sink some damage into the Captain, a Guardian should utilize Anti-Overload rounds obtained from the Seasonal Artifact to shut down their ability regeneration and stagger the powerful Fallen champion.
List of appearances