The Master scans through his own sizeable brain for anything relating to the Yeerk's. He holds the one he still has a firm grasp on into the sickly light.

"They're not native to our reality. Blind, but compensate with pedipalps," ho-hum, he rips those off so that if it gets loose it's pretty much lost. When he does so, he recoils, planting a finger from his free hand into his ear, "Ow. Apparently communicate through ultrasound. I'm not fluent, so let's try something else--"

Mind contact was always his strong suit, and he even had a physical channel. The thing thrashes in his hand momentarily, before dying down.

"... Of course! Oh you clever little thing, you!"