The guardian speaking to Ratchet
The guardian was a colossal mining robot formerly built by the fongoids and repurposed by the vullards, that guards the Hollow, in Monoloth Fields. He knew where Azimuth dwelled but did not allow Ratchet through, stating that outsiders must find their own way. The Guardian was in reality a vullard operating the old mining robot by using a control panel, who later lead Ratchet to the Hollow. The head of the guardian was exactly like the one that Alister lived in. A pressurized system could've been used to make the mouth move because steam could be seen spraying out a pipe in the mouth.