A max level, imprinted mosa with a high armor saddle is virtually unstoppable. I had a green one that I bred and named Jormungand after the world serpent in Norse mythology. It’s strength was mythical! (No pun intended)
Great all around underwater. Powerful and tanky. I have noticed they are able to survive a jelly fish swarm. I have mine kill around 40 jelly fish while being shocked.
My mosa has 14K HP and over 300 melee with an acendent platform saddle and he can kill anything in the ocean. Even alpha Mosasaurus and still have 13K health. (I play mobile.)
These creatures in real life actually needed to surface to breath much like whales, also they stayed near the surface of the water, never straying to deep.