Take the tour ×  There's a module which features an inanimate
object without a Will defense.  Does a lack of Will defense mean
you can't attack the target with a power that goes against Will?
Or you can but it automatically misses? Or you can but it
automatically does no damage?  I'd prefer RAW. However, how
should a DM handle this if a player does attempt an attack?
share|improve this question add comment  2 Answers  up vote 11
down vote accepted  Rules Compendium p 176:  Object Immunities,
Resistances, Vulnerabilities  Unless otherwise noted, an object
has immunity to the following: necrotic damage, poison damage,
psychic damage, and any attack that targets Will.  That should
give you your RAW answer. This is not universal, but when an
object does not have a Will noted it is immune to attacks
against Will.  share|improve this answer Isn't the "1 always
misses" rule still technically an optional rule in 4.0? – 
Zibbobz Sep 23 at 13:29 @Zibbobz not that I know of. Also note
the complete reversal in answer. –