Who is more aggressive Rock or Retic?

[Annarose15]

Im trying to find out who is more aggressive and who is the biggest of the two and can they breed together? I was watching Swamp Wars and they had a huge Rock on there and they always have Burms thats would be scary if these guys can breed together.

I don't understand what makes the hybrids so much more "scary" than the pure form. They are both big. In the wild, they are both aggressive. In captivity, rocks appear to be much more aggressive than retics or burms. How is crossing one big snake with another more "scary" than the original big snake?