Research. Fairy tales involving interesting creatures.

I have started looking for Fairy Tales that I can use or adapt for my final project. I know that I want a story that includes some interesting creatures as I really want to challenge my puppet sculpting ability further than normal human puppets. I also need to be careful that I don't choose a story that involves more than 3 or 4 puppets, as more than this would be difficult to get done in the time I have for this project as well as animating it. 

I have a Grimm's Fairy Tale book that I have started skimming through looking for good stories. I have decided to stick to Grimm's fairy tales as many of them are well known in some form, and they have a tendency to be quite dark and twisted, which is exactly what I am looking for and am interested in for this project. 

So far I am looking at a few stories, including Hansel and Grethel, Billy Goats Gruff, and Rumplestiltskin, as these are all quite dark and including few characters. I think that these stories would be really interesting and haven't been animated too many times in the past. I would be able to adapt the characters in these stories to make them include more creatures like goblins and trolls and ogres, or they have the ability to make massively over exaggerated characters (like the witch in Hansel and Grethel). 

I am leaning more towards doing Rumplestiltskin at the moment as I think the Rumplestiltskin character would be well suited to being a Goblin as they're both known for being mischievous.