The sea monsters were far too stiff. Now every creature moves its own way: fish, eels and the Mist Serpent ripple side to side, rays beat their wings, crabs work their legs and claws, the Basalt Turtle rows with its flippers and the octopus spreads its tentacles.
The rhythm follows their speed: standing still, the beast only breathes; swimming fast, it moves harder.
And whatever bites now lunges: the head surges forward and up, or the tentacles rise, at the moment of the strike. Keep an eye out.
If you play with reduced effects in the Options, creatures stay still as before.