Here is a photo of the raw materials - lots of Lewis Newplast in a range of colours. The greeny grey mushroomy things at the bottom are hardened epoxy putty over some nuts. These will form the core of the clay blobs and act as tie-downs, fixing the puppets to the set floor. The things in the packet at the top are rubber tipped modelling tools, which I ended up hardly using on these puppets, as the shapes where so simple.
These are the basic shapes of the alien blobs. They don't look like they took long to make, but they took all night, because Newplast is so hard. I had to knead small strips at a time to make it malleable enough to work with, yet I still ended up with sore bruised patches on my palms the next day from working with it. The price you pay for using a clay that won't go mushy under hot lights.
I thought about brushing down the surfaces with a quick-drying solvent to smooth out any lumps, bumps and fingerprints, but I decided I rather like the fact they are a bit rough and ready and imperfect - after all, most living creatures are!
For these puppets I decided to make the eyeballs out of polymer clay (Fimo Soft) instead of just painting pupils on beads. I rolled white clay into balls, baked them in the oven until they were hard, then added pupils with black clay, put pin holes in them to help with movement, then baked them again.
This is Big Blob without his mouth. His antler thingies are made of hardened Fimo Soft, and most of the details are made of Flair Plasticine (softer and more melty than Newplast, but has brighter colours).
Here is a photo of the whole colony of alien blobs. I'm pleased because they look exactly how they did in my head before I made them. The little purple one is all Flair Plasticine and has no tie-down because he is going to scoot about a bit.
Now I think it's time for a cup of tea, then back to making mouths for them...