Husnock

The Husnock were a sapient, but extremely hostile spacefaring species. In 2366, they became suddenly extinct following an attack on the Human colony of Delta Rana IV. Unbeknownst to all, one of the colonists was in fact a Douwd who, due to his pacifist ways, opted not to use his powers to wipe out the invaders. However, after his Human wife was killed while defending the colony along with the others, the Douwd couldn't bear the grief and in an impulse of anger destroyed not only the attacking Husnock ship but all 50 billion members of the Husnock species everywhere.

Appearances

 * Star Trek: The Next Generation, s03e03, "The Survivors" (1989)