This is easy enough to solve if you use a cloned horse that has had some CRISPR genetics done so that it now has fish gills and can breathe as normally underwat

This is easy enough to solve if you use a cloned horse that has had some CRISPR genetics done so that it now has fish gills and can breathe as normally underwater as it can on land. You probably drown a few horses before you find one that swims well but, as we all know, once you identify that one horse that can manage that feat you have a monopoly on the game.