There's a pirate feast chasing Briggid, underleveled units will enjoy leveling up on them. Oh, and Tiltyu is underleveled, and in the vicinity of the pirate feast.
RETREAT BRIGGID TOWARDS CLAUDE AND TILTYU. You should be able to find a nice spot for Briggid to wall them. I didn't find them walking on water a problem, since they do it so slow.