Viith Yalu was the Master Shaper sent by the Yuuzhan Vong to command the Damutek facility on Wayland during their invasion of the New Republic. The Wayland facility was one of several Shaper projects looking for ways to understand the Force and defeat the Jedi, but Viith Yalu's most notable success came not through Shaper bioscience, but through making contact with Bey Gandan, a Jedi prisoner who was sent to the system as a slave, and who seemed to have already been crazed with jealousy and hatred due to his comrade Klin-Fa Gi's relationship with Yabeley.
Willingly joining forces with the Yuuzhan Vong, Jedi Gandan allowed Viith Yalu to implant a villip in his brain, and conspired with him to serve as the invaders' agent in a plot to sabotage bacta production on Thyferra. The bacta plot was foiled by Klin-Fa Gi and Uldir Lochett.
- The Complete Star Wars Encyclopedia