Ugly creature of folklore (5)
I believe the answer is:
troll
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">ugly creature of folklore</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for troll that I've seen before include "Fish by pulling a hook, line and sinker" , "who's stirring on-line" , "unwanted contributor to site?" , "Online annoyance" , "Internet provoker; ugly being" .)