For science-fiction or fantasy characters or creatures, the cardinal rule is to make their names readable and pronounceable. Even if you were never into comics, you probably remember Jor-El, Superman's dad.
By contrast, if you name your hero Lohrates, your reader will spend the book going, "Lor-AY-tees? LOW-rates? La-RATS?"
A hard-to-read name is an excuse for a reader to put your book down.
Jean Auel did a good job of naming her prehistoric characters in her Earth's Children series (The Clan of the Cave Bear, et al.): Ayla, Ranec, Broud, Durc, Jondalar.
If you feel wedded to a particular unusual name, at least let the reader know how it sounds by having a character pronounce it, or let your narrator do it.
Writers of sci-fi tell me they use foreign-language dictionaries when they're trying to come up with names. For instance, you could name your shape-shifting monster Modir-Rettr, which is Old Norse for 'mother-in-law.' (Roughly.)
You can also work wonders by changing one or two letters in a common name or a word, or adding a hyphen or initial. Mess around and see what sounds good, and discover what works best for your story.