Area: The wall of iron is one quarter of an inch thick per level of experience of the spell caster.
The magic-user is able to evoke an AREA of iron wall 15 square feet for each of his or her experience levels,
Area.DMG: If the caster concentrates specially, it is possible to double the area by halving the thickness.

Effect: When this spell is CAST, the magic-user causes a vertical iron wall to spring into being.
Typically, this wall is used to seal off a passage or close a breach,
    for the wall inserts itself into any surrounding material if its area is sufficient to do so.
If the wall is created in a location where it is not supported,
    it will fall and crush any creature beneath it.
The wall is permanent, unless attacked by a dispel magic spell,
but subject to all forces a normal iron wall is subject to, i.e. rust, perforation, etc.

Falling wall of of iron.DMG: If the wall of iron is created vertically,
    there is a 50% chance either way for its falling left or right,
    ahead or backwards, depending on its placement.
    It would take not less than 30 strength points
    with at least 400 pounds mass to affect this probability,
    and then only 1% for each pound over 300 or strength point over 30.

MC: A small piece of sheet iron.

Area.example: so at 12th level a wall of iron 180 square feet in area can be created.
 

Wu Jen: The wu jen casting this spell creates a vertical wall of iron, 1/4 inch thick per level and covering 15 square feet per level of the caster.
It fills a passage tightly if it is cast in an area where it can do so, otherwise it topples over, crushing creatures beneath it.
There is a 50% chance it topples either way, modified by 1% for each 300 lbs. over 400 or Strength point over 30 pushing on it.

MC.Wu Jen: An iron bar.

Wall of Iron, Wall of Stone: PCs would be
aware that using these spells can raise
certain problems regarding the stability of
the wall, notably when using wall of
stone to bridge chasms, etc.  Details are
found in the DMG and players should
negotiate with DMs about how much
exact information their PCs can be ruled
to know.  Unfortunately, neither the PH
nor the DMG tell players how much
damage a falling wall will do to creatures
crushed beneath it when the spell is used
as an offensive weapon (walls of iron can
automatically be created in the air; walls
of stone only have to merge with an
existing stone formation at 1 point, and
the PH states that they do not have to rest
upon any firm foundation).  Logically,
such information should be part of the
knowledge characters receive when they
are taught the spell.
(Imagine #29)

Bombay wrote:

Gary, a situation has come up with a enemy mage casting Wall of Iron above one of the players heads.

What the damage should be as it falls is the question. He thinks it should be 10-100. I think that is way too high considering the level of the spell(5th). It isn't a death spell.

If you look at wall of ice(3-30) and that is a 4th level spell, perhaps wall of iron would be 4-40 or 5-50??

Daerns instant fortress is 10-100 and its 20x30 on one side. So this wall of iron that is free falling onto the player is 10x15. Roughly 50% the size of one wall of a Daerns instant fortress.

Curious what type of damage you would have this cause to a player in your game.
 

Gary wrote:

I did not allow a wall of iron to be CAST unless it was anchored on at least three sides.

Thus a damage question never arose.

Cheers,
Gary