[MaxWilson]

Well, since you're Vanheim you can forge underwater items pretty easily (Pills of Water Breathing, Barrel of Air), so the underwater part isn't really a factor. Unfortunately you have no astral casters for Antimagic, and the troops you have tend to be elite-but-few. On the plus side Vanheres should chop right through Mind Lords even with e.g. Ironskin, Luck, and Body Ethereal cast. That's about as far as my experience can take the analysis.

-Max