User blog comment:The1nonley/is the krakken an alien?/@comment-8505655-20130608144448

Even if the kraken is an alien, if it is not sapient, the omnitrix will not scan it.

Anyway, I would posit that it is neither an alien nor a dinosaur. It seems to be native to earth, and its attributes suggest that it is an amphibian rather than a reptile. Really, it is simply a terrestrial animal unknown to the scientific community, or a cryptid, to use the fancier term.