I used a pair of ooze-like critters as part of an adventure involving a low level necromancer. She would save every part of the people she killed, using unique procedures to preserve and animate the blood as one undead ooze, the skin as another undead, the skeleton as a third, and the viscera/muscles as final undead ooze.
The blood 'oozes' were made of 10+ pints of cold blood that attempted to grapple living targets and blind them. Once they got a pin, they could attempt to drown / suffocate them. They were also fairly resistant to damage, being animated liquid. They were only half a HD, so when an attack did affect them, they were pretty much toast.
The viscera 'oozes' were made of everything else, the muscles, the veins, the organs, etc. all lurching along through muscular action, lashing out to drain blood and attempt to digest living targets with digestive acids. They had 1 HD, and were fairly easy to hit, but could restore hit point damage via their blood drain attack. The necromancer considered the Viscera a failure, and kept them locked in ceramic tubs, since they tended to drain blood and rot flesh with their acid secretions, which cut into her supplies of materials for later research and animation.