As many already know, the powers of the Titans in the anime Attack on Titan (Shingeki no Kyojin) originated from an aquatic creature after Ymir Fritz was hunted and fell into a tree.
Therefore, we researched this creature and found something similar in real life, that is, a direct resemblance to the story of Attack on Titan written by Hajime Isayama.
Check it out:
The same creature existed on planet Earth under the name "Hallucigenia," approximately 513 million years ago, according to sources. Interestingly, the creature was discovered through articulated fossils and volcanic ridges.
Finally, we cannot confirm whether the author Isayama used the creature as a basis for his acclaimed story of the Titans.