If Kaido is revealed to not be the strongest, then okay. You expect me to cry about it or something?You will take your words back when you get to know Kaido is not the strongest OP character. By creature it meant animal (not Human). It's been used as a rhetorical term
And I know what Humans are, One Piece is not science, Oda doesn't care about science in manga
Oda cannot use words for a different meaning than what they are unless it's a form of metaphor or hyperbole, and so far, Kaido's title hasn't been portrayed as either. If Oda says Kaido is the strongest creature alive, then until he either retcons that title, or reveals it to be hyperbole, then it means he's the strongest creature alive, plain and simple. It's not about science, it's about language, and if you say Oda doesn't care about language, then you shouldn't be posting here.