I have already made several Cthulhus with this free pattern from Cthulucrochet http://cthulhucrochet.blogspot.de/2008/05/tiny-cthulhu-free-pattern.html
I'm a big fan of Doctor Who and so, one day, I thought I could easily make an Ood with this pattern. I only needed to use other colours and made some very small adjustments to the pattern (and of course didn't make the wings).
I used a DK cotton yarn and a 3,5 mm (E) hook. You can use thicker or thinner yarn, this will only change the size of the Ood.
Skin coloured yarn (for head and hands)
Red yarn (for tentacles)
Blue yarn (for body)
White yarn (for ball)
Safety eyes if you have any (I just embroidered the eyes)
Some small decoration stones (used as filling at the bottom to make it stand better)
Follow the original pattern and use the colours mentioned above.
Change I did:
When you are supposed to do the tentacles, switch to red yarn and "chain 6, 3 sc in third chain space from hook, 3 sc in each of next 3 spaces". Switch back to skin coloured yarn.
Use white yarn.
4 sc in magic ring (leave a long tail)
RND 1: work 2 sc in each st around (8 stitches)
RND 2-3: work 1 sc in each st around (8 stitches)
RND 4: work dec in each st around (4 stitches)
Finish off, leave a long tail and use it to sew the ball to a hand. Use the long tail from the beginning and sew it to where the mouth is supposed to be.