The Thing vs the Blob

Connection:

Both are live action, antagonistic shapeshifting entities from space (The Thing is an alien whilst the Blob is either an alien as well or an experiment mutated in space by radiation) which hunt, assimilate and devour humans with their unique biology after arriving from space

Both bear names which reflect their lack of a solid form or identity

Both also have a habit of hiding in plain sight or misdirecting with human disguises via the ones they have, or are in the process of, killing

Both also utilize acid in some manner, are weak to the cold, which has led to their imprisonment at some point, particular in Antarctica, and are essentially living cells

Both are also vulnerable to opposite elements (The Thing is weak to fire and The Blob is weak to ice)

Coincidentally, both share their names with Marvel characters