Ygziir was a planet in the Yuuzhan Vong galaxy that was home to a domain allied to Warmaster Steng, possibly his own. It was destroyed in the Cremlevian War, together with its moon.

The rival Warmaster Yo'gand's domain used a large dovin basal to pull the moon into the planet; it would later become known as the Yo'gand's Core tactic. Steng's domain either surrendered or was wiped out. Considering the protocols of the Yuuzhan Vong, the latter is the more likely.