The sibling of Marn Hierogryph was a Snivvian male from the Galactic Republic who made pro-Republic propaganda broadcasts during the time of the Mandalorian Wars.
He used the alias "Captain Benegryph Goodvalor," a name given to him by his brother, Marn Hierogryph, for the Ministry of Defense after the battle of Serroco. During that battle, Marn and his Trandoshan companion Slyssk accidentally rescued about half of a battalion of soldiers, which the Defense Ministry decided to use as a propaganda opportunity.
Hierogryph's sibling was selected to deliver the propaganda broadcast. These broadcasts were transmitted using a directional transmitter, and they flooded the Z-band frequency of subspace radio, which the Mandalorians used to communicate among their ground forces.
In his broadcasts, "Benegryph Goodvalor" professed to be the captain of a huge new Republic warship called the Serroco and implored the Mandalorians to give up. He described enormous Republic fleets preparing for a coming counteroffensive that would shift the war in the Republic's favor. He also spoke at great length about the luxurious accommodations on his ship and the high quality of life enjoyed by Republic citizens.
His broadcasts usually started with the phrase "Attention Mandalorians!" and finished with a short saying that praised the Republic. Examples of these sayings were "The Republic. Here today, here tomorrow" and "The Republic. Real beds. Running water."
After the capture of Taris, the Mandalorian strategists decided to focus on the nearby planet of Zongorlu. Goodvalor had foreseen this and cautioned the Mandalorians against attacking. He claimed on several occasions that Zongorlu was a scorching volcanic planet with acid rain; that the native Zongorlu were furious at the Mandalorians for destroying youngling camps; that the Zongorlu system had so many Republic warships that traffic was becoming a problem; and that the Serroco was in orbit above a massive citadel on the planet.
The Mandalorians were cautious during the assault on Zongorlu, but they did not meet any resistance. They found that Captain Goodvalor had been operating from a small transmission station on the surface, but had escaped long before the Mandalorians got there. There were a few abandoned ships in orbit around Zongorlu, but no Republic fleet. And the Zongorlu species were not the fierce warriors that Goodvalor had described, but a slow, peaceful plant species that could barely move a meter each day.
The Z-band was clear of interference for a few days, but then Goodvalor returned to the airwaves with his usual greeting, claiming that he had been unexpectedly called away from Zongorlu before the attack. Goodvalor's message had changed from demanding unconditional surrender to suggesting a peace agreement, including a share of taxation for all Republic planets under Mandalorian occupation.
During one broadcast, someone who claimed to be "Commander True," Goodvalor's first officer, relayed the captain's apologies for his absence. Regardless, the Mandalorians were not impressed by him. They continued to use the Z-band despite his broadcasts. Many Mandalorians reacted by turning off their transceivers, which caused some minor communication issues. Mandalorian signals expert Koblus Sornell acknowledged that the broadcasts were affecting some of the newer, less dedicated recruits, but insisted that any true warrior would simply ignore them.