How about a hydra? Regeneration. Seven heads, each with a different dameage type (cold, fire, acid...?)

a hook horror maybe

Does anyone have any experience creating monsters?

<font color = lightgreen>Not much experience, here; I tried creating PeeWee's Blink Dog. From ShadowKeeper I edited a War Dog: bumped it up in power a little bit, added some innate spells, and then saved blinkdog.cre. Adding this .cre file to the override folder let me get the dog into the game, so this is probably the easiest method. Luvian seems to be a bit more advanced at this than I am at this point; seek out some of his posts.</font>