
Green Lantern Sodam Yat was a rare exception. They ban space travel, indoctrinate their children with fears of aliens, and teach them that Daxam is their entire universe.
The Daxamites of The DCU are a ridiculously xenophobic society. There are Termights who object to Torquemada and his Terminators however, and he's eventually overthrown by the human resistance with help from Nemesis. The Termight in Nemesis the Warlock is on a perpetual crusade to wipe all non-human sapient life from the galaxy.
Oh, and they also shoot it with a Big Bang for good measure. In the end, they defeat it by giving it a fit of horror at being mentally contacted by the entire human race. The moment Professor Xavier tries to make contact with it, it spasms with revulsion and opens fire on Earth. Oddly enough, this loathing is almost completely irrational.
Gah Lak Tus, the Ultimate Marvel Galactus, is a fleet of killer robots motivated by a thorough loathing of all organic life they don't just try to kill everything fleshy, they do so in the most hideous and painful ways they can come up with. Even then, he's just saving them for last. Out of eternal hate, he finds other living things appalling- save for those that worship and follow him. Unicron, the God of Evil of the Transformers, has made it his final goal to wipe out all creation and leave nothingness in his wake so he may be at peace in an endless void.