Pit of Shades

The wizard opens a rift to the infamous Pit of Shades.
Terrified warriors fall screaming through the portal,
plummeting to a shadowy noplace filled with the
incessant wailing of 'those who dwell beyond'.
Pick 1 enemy unit within 18" of the caster that
is visible to them and roll 2D6. If the roll is
higher than that unit’s Move characteristic, that
unit suffers a number of mortal wounds equal to
the difference between its Move characteristic
and the roll.