Changed my mind about legs, and some other stuff...
step 3 of 5
Used bones and HD solver to rig the legs, and dummies with look at constraint to rig the pistons...
step 4 of 5
Used vray for rendering...
step 5 of 5
Used photosho cs4 for lights and steam effects, just used pen tool to make a selection and applied gaussian blur. Then coppied to multiple layers with various blending modes...