Building with Berbils is a TV show that was featured in the ThunderCats Roar series. It is an instructional show in which a Berbil teaches viewers how to build various things using various tools.
The Driller is shown watching this show inside Cats Lair after he becomes disheartened with his existence. While conducting the show, the Berbil host notices his drill doesn't work. Opening it he sees that it is completely empty and considers it to be pointless, mirroring the Driller's feelings.