Smooth flowing swimming in unity using custom inverse kinematics and additive animation

This flowing movement was created using a custom inverse kinematic (IK) system with additive animation. In reality the head of the player is the object being controlled while the IK system is what lets the rest if the body flow behind. Using cone based constraints to lock the players joints into a realistic range of motion and some additional dynamic roll rotations the movement can look very smooth.

I did not create or rig the player model