Stuff

The Stuff is the titular villain of the 1985 sci-fi horror film "The Stuff" and is similar in some ways to both the Xenomorphs and The Blob as it is a parasitic life-form that exists under the ground but becomes deadly once eaten and will grow to the point of killing its host: it is also extremely addictive and can take control of its victims minds, forcing them to attack those that would seek it harm.

The Stuff also has a strange, very sweet taste that humans seem to enjoy - this made The Stuff especially dangerous as it was mistakenly sold as a foodstuff and even an ice cream by unwary businesses, resulting in the deadly substance being unleashed upon an unsuspecting public: with gruesome results.

The Stuff is the titular villain of the movie but the true antagonists are arguably Mr. Evans and Mr. Fletcher - two rival businessmen who were willing to sell the Stuff in order to profit of its addictive properties despite knowing of its deadly origins.