I've been making stats for some new monsters for my GURPS DF game recently.
The hardest part for me is naming them.
If I start with a good name, it's easy. For example, Death Brain. Slugbeast. Leaping Leeches. Eye of Death.*
Others I start with a concept, or a miniature, or a visual image, but need a name.
That's the hard part.
A good name is evocative, and tells you something about the monster either clearly and correctly or in an indirect way. Rocks trolls, for example, aren't trolls, but they are regenerating rock men, which fits the name. Phase serpents do exactly what it says. Dinomen are little dinosaur-headed lizard men. Spheres of Madness are spheres and you can sure tell why someone added "of Madness!" to the end of their moniker for theese multi-eyed, tentacles, head-eating things.
Sometimes, though, I just don't have a good name. Nothing that'll beat out the the inevitable disparaging nickname ("Derps") of the PCs, or inappropriately vague identification ("land monster.")
That's where I am stuck on a few monsters. Great concept, great minis (for at least a couple of them), and nothing like a good name that the PCs will actually like and use.
I'd ask for help, but then they wouldn't be a surprise. I may just end up with Derps II or Derps Junior for lack of an evocative name that the players like and use.
* Which was also inspired by needing giant flying killer eyeballs. I've been asked if it's a Beholder ripoff. No, it's a giant flying eyeball. My flying biting sphere monsters with eyes on stalks and a big anti-magic eye are beholder ripoffs. Heh.