Enlarge & Reduce Spells

[Samothdm]

I have a questions about reduce and enlarge spells. I've been DM'ing a group with no spellcaster but a new player just joined and wants to play a wizard.

His idea is to take reduce and enlarge spells and do the following:

1) Enlarge. Specifically target an opponent's weapon so that it becomes so heavy that the opponent can't lift it or wield it effectively.
a) Can you be that specific with the target of an "enlarge" spell?
b) Does he need to make a "ranged attack" to hit someone (or something) with this spell? (the rules don't say that he has to, but then again "magic-missile" says it automatically hits but enlarge doesn't specify that so I'm not sure which way is right)
c) If he does need to make a ranged attack, could he combine enlarge with a quickened "True Strike" spell to make his attack more accurate?
d) Also, if he needs to make a ranged attack, by trying to hit his opponent's weapon would he take the penalty associated with attacking a weapon?

2) Reduce. He wants to use this to shrink an opponent's armor so that the armor will slowly crush his opponent and cause him damage.
a-d) Basically, same questions as above, plus:
e) If he can use the spell this way, how much damage would that cause?

I looked through the FAQ and couldn't find answers to these questions. I hope they're not too dumb but I don't have a lot of spellcasters in my game so we've never encountered this before.

Thanks in advance.

 

[AuraSeer]

1a) Yes, you can be that specific. Note that since the target is in use by a creature, the creature gets a saving throw against the effect.

1b) No attack roll is needed. The stat block for Enlarge says "Target: One creature [etc]." If the spell created a ray, it would instead say "Effect: Ray". (See the spell Enervation for example.)

1c) True Strike works on your next attack roll, no matter what kind of attack that is. So if after casting True Strike, your next action was to cast Ray of Enfeeblement, you would gain the +20 to hit with your ranged touch attack. Note that this does not apply to Enlarge: see 1b.

1d) Yes, when you cast a ray spell on a weapon, you are subject to modifiers for attacking a weapon. Note that this does not apply to Enlarge: see 1b.

 

[MeepoTheMighty]

2) Reduce. He wants to use this to shrink an opponent's armor so that the armor will slowly crush his opponent and cause him damage.
a-d) Basically, same questions as above, plus:
e) If he can use the spell this way, how much damage would that cause?

You can't use the spell that way. From the SRD, "a shrinking object may damage weaker materials affixed to it, but a reduced object shrinks only as long as the object itself is not damaged."

Newton tells us that the armor can't damage you without you damaging the armor. (Think of the incredible hulk bursting through his shirt, but in reverse.) Therefore the armor can't shrink, since doing so would damage the armor.

 

[dcollins]

2) Reduce. He wants to use this to shrink an opponent's armor so that the armor will slowly crush his opponent and cause him damage.

Wow, that's only been banned from the D&D game since at least 1979.
(1st Ed. AD&D DMG, p. 44, "it is not possible to 'squeeze someone to death in their armor'".)