[Snake]

A fine concern, but it ain't really that realistic to make happen given how attacks work. I don't think it's necessary but a better visualization of how it could be implemented would revolve granting Spirit Mirror's reflect ability if an unit is standing within one square of a Water Wall, while under the effects of Ensui Veil.

The attack would be reflected, and the water wall would be destroyed as Ensui Veil's duration is reduced by 1 round.