Concealment loss advancing to higher elevation


Senior Member
Jun 24, 2013
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central WI
In the past I have always played that a unit assault moving or advancing to a higher elevation into either Concealment Terrain, or provided with Height Advantage in otherwise Open Ground, would retain its concealment. Upon reading the following I think this may be incorrect when a unit crosses an Open Ground hexside fully in LOS of a Good Order enemy ground unit:

12.14 REMOVAL:.....
A concealed unit’s “?” is also lost immediately if it does any of the following in LOS of a Good Order enemy ground unit within 16 hexes (such potential LOS checks are free and require no attack or penalty for a blocked LOS):
- moves/advances/withdraws into an Open Ground hex (as defined in 10.531),...

A10.531 OPEN GROUND: For purposes of rout determination, Dash, concealment gain/loss, and Interdiction, an Open Ground hex is any hex in which the particular enemy unit(s) could apply, during a hypothetical Defensive First Fire opportunity (regardless of what attacks it actually made in previous phases), the -1 FFMO DRM. .....

B10.31 HEIGHT ADVANTAGE: a moving unit being fired on by Defensive First Fire is not eligible for the Height Advantage TEM if in entering the target hex it crosses a Crest Line through the same hexside that is intersected by the firer's LOS.

Also see the example following this rule.

Which leads to the question...does a unit lose its concealment if it assault moves/advances across an Open Ground hexside to reach the higher elevation if a Good Order enemy ground unit can see the entire hexside without any hindrances?