The New Republic seized and repurposed an Imperial Viper probe droid, which they designated BALK1, for their own purposes. When the New Republic grew suspicious of Imperial actions on the planet Akiva, this probe droid was dispatched to gather intelligence. It determined that two Republic A-wings previously deployed to the system had been destroyed and that planetary communications were blocked, but it could not definitively confirm an Imperial presence. Although this information was insufficient to justify a full-scale New Republic assault on the system, a message later transmitted by the captive pilot Wedge Antilles verified the Empire's presence, leading to their expulsion from the system by a New Republic fleet.
Arakyd Industries, a droid manufacturer, originally produced the Viper probe droid BALK1 for the Galactic Empire. The New Republic subsequently acquired and reprogrammed it for their own use. Some months following the Battle of Endor, the New Republic received information from an Imperial informant known only as the Operator, alleging that high-ranking Imperials were convening at a secret summit on the planet Akiva. Fleet Admiral Gial Ackbar, initially skeptical, dispatched two A-Wing starfighters to Akiva. The planet was already under consideration by the Republic in their search for the pilot Wedge Antilles, who had disappeared while scouting in the region.
After the two fighters failed to report back or return from Akiva, Ackbar gave the order to send BALK1 to investigate their fate. Ensign Deltura and science officer Niriian launched the droid from the Carrack-class light cruiser Oculus, which was located near the remains of the comet Kinro. Upon leaving the ship, BALK1 immediately commenced transmission of atmospheric data back to the Oculus as it approached Akiva, which was visible from the cruiser. After a journey of six hours, the probe droid arrived at its destination and initiated scans of the Akiva system. While it detected no Imperial vessels, it identified molecular remnants confirming the destruction of the two A-wings. Upon receiving this information, Ackbar instructed Deltura to have the droid attempt to ping Akiva's comm relay, but BALK1 was unable to establish contact due to an Imperial communications blackout on the planet. Although concerned, Ackbar did not consider this sufficient cause for immediate action. Antilles, who was alive and imprisoned on Akiva, eventually managed to send a message to the New Republic confirming the Imperial presence. A New Republic fleet then deployed to the system, defeated the Imperials, and forced the survivors to withdraw.
BALK1, as a Viper probe droid, was equipped with five spider-like limbs attached to a body featuring a dome-shaped head and a set of retrothrusters for spatial maneuvering. These limbs retracted into the body during space travel and extended for stabilization. A set of antennas, located in the droid's head, could also be extended when the droid was stable, and were designed to take measurements. The droid was capable of scanning a star system to the molecular level and identifying molecular components with enough detail to establish the make of a destroyed vessel they originated from. Dentura and Niriian controlled the droid remotely from a Carrack-class cruiser located in the same star system, and received data and encrypted communications from the droid which sounded like a strange song when played aloud.
BALK1 made its debut in the 2015 novel Aftermath, authored by Chuck Wendig.