What happens when the rider of a soaring cavalry unit is overwhelmed.Is he eliminated, or placed in contact with the flying base?

eliminated

Thanks Ares

Unless the rider can also use the soaring proficiency (and so far none can), the rider falls to the ground and goes KER-SPLAT!

The same thing happens if a cavalry unit is in deep water and the rider is dismounted. If he doesn't have the :aquatic: movement type, he drowns.