I use Leaping shield as a shield wall breaker as well but as part of the extended contest but the defenders get heavy improv. mods to defend against it unless they have something appropriate like spit down wind.
Re spit down wind I am leaning more towards this as a unit used volley attack to defeat wind powers. This is seems to more in line with the Lunar \Solar ideas of taking power away from individuals and place it with the unit\mob where it can be more easily controlled by the leaders.
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