The Dipthodat are a spacefaring race of extremely xenophobic creatures which feed on the negative energy generated by feelings of discord among other races. They physically resemble bipedal sheep with fish-like facial features, but also have some aspects reminiscent of a squirrel and a pumpkin. When dealing with non-spacefaring species, they naturally disguise their real appearance by technological means.
The Dipthodat build their houses out of a secreted organic polymer, somewhat similar to sugar, which according to Nyssa, might have originated the folklore tradition of witches living in candy houses in some Earth cultures. In the mid 20th century a group of Dipthodat arrived on Earth and sold enslaved Veritans (a.k.a. "Truth-Tellers") to the locals, causing them to speak unpleasant truths aloud and generating loads of negative energy for the invaders to feed on.
- Tip of the Tongue, by Patrick Ness (2013)