The Kelpie, Lord of the Deeps

Partner with Dianaimh, Lady of the Isles.
As long as The Kelpie, Lord of the Deeps is on
the battlefield, Dianaimh, Lady of the Isles has protection from creatures
"She lay in the arms of a strange creature,a pale horse
who's coat glistened with slime, with hoofed feet and a flowing white mane..."