From Podpedia

Warblers are the lowest tier combatant void godling present in Sha-Lai during the events of a Celestial Crusade. They had the ability to appear to be normal humanoids using a visual illumination, but couldn't mask their nature against touch. The warblers appeared to be humanoid at first glance, but instead of a face, they had y shaped lips covering radial teeth. They also bent their joints unnaturally. In combat they could engage with bare handed melee, or they could use a warbling scream that gave them their name.