Cover and hitting cover
Reginald Blue
Consider this text from the SRD:
--
Reginald Blue
"I have always wished that my computer would be as easy to use as my
telephone. My wish has come true. I no longer know how to use my
telephone."
- Bjarne Stroustrup (originator of C++) [quoted at the 2003
International Conference on Intelligent User Interfaces]
Reginald Blue
> So, I'm pretty sure I know the answer but...
>
> Consider this text from the SRD:
Hate it when I hit the wrong key like that...
Text from SRD:
"To determine whether your target has cover from your ranged attack, choose
a corner of your square. If any line from this corner to any corner of the
target's square passes through a square or border that blocks line of effect
or provides cover, or through a square occupied by a creature, the target
has cover (+4 to AC)."
The question is, if you miss by the amount specified by Cover, do you hit
the Cover? I'm presuming the answer is "no", but I am understandably
curious as to what other people do in their games.
Marcel Beaudoin
> Reginald Blue wrote:
> > So, I'm pretty sure I know the answer but...
>
> > Consider this text from the SRD:
>
> Hate it when I hit the wrong key like that...
>
> Text from SRD:
>
> "To determine whether your target has cover from your ranged attack, choose
> a corner of your square. If any line from this corner to any corner of the
> target's square passes through a square or border that blocks line of effect
> or provides cover, or through a square occupied by a creature, the target
> has cover (+4 to AC)."
>
> The question is, if you miss by the amount specified by Cover, do you hit
> the Cover? I'm presuming the answer is "no", but I am understandably
> curious as to what other people do in their games.
My DM rules that if you would have hit, but the cover bonus to AC
makes you miss, you hit the cover.
Marcel
Reginald Blue
What if the cover is a person? Do you auto-hit the person, or do you need
to go into some new resolution mechanic of overcoming that person's AC?
or...?
Marcel Beaudoin
> Marcel Beaudoin wrote:
> > On Feb 20, 1:46 pm, "Reginald Blue" <Reginald_B...@hotmail.com> wrote:
> >> Reginald Blue wrote:
> >>> So, I'm pretty sure I know the answer but...
>
> >>> Consider this text from the SRD:
>
> >> Hate it when I hit the wrong key like that...
>
> >> Text from SRD:
>
> >> "To determine whether your target has cover from your ranged
> >> attack, choose a corner of your square. If any line from this corner
> >> to any corner of the target's square passes through a square or
> >> border that blocks line of effect or provides cover, or through a
> >> square occupied by a creature, the target has cover (+4 to AC)."
>
> >> The question is, if you miss by the amount specified by Cover, do
> >> you hit the Cover? I'm presuming the answer is "no", but I am
> >> understandably curious as to what other people do in their games.
>
> > My DM rules that if you would have hit, but the cover bonus to AC
> > makes you miss, you hit the cover.
>
> What if the cover is a person? Do you auto-hit the person, or do you need
> to go into some new resolution mechanic of overcoming that person's AC?
> or...?
So far, we haven't run into that problem, although I think the DM has
said that if it is an enemy, he would check the to-hit roll against
the enemy's full AC. If it is an ally, then I think he said it would
be against flat-footed AC.
This could be a problem in our campaign as my character took the
Grenadier feat and is quite fond of using moltov cocktails.
Marcel
Jasin Zujovic
> > > My DM rules that if you would have hit, but the cover bonus to AC
> > > makes you miss, you hit the cover.
> >
> > What if the cover is a person? Do you auto-hit the person, or do you need
> > to go into some new resolution mechanic of overcoming that person's AC?
> > or...?
>
> So far, we haven't run into that problem, although I think the DM has
> said that if it is an enemy, he would check the to-hit roll against
> the enemy's full AC. If it is an ally, then I think he said it would
> be against flat-footed AC.
That sounds weird. You you're poking a spear at someone and I (your
ally) step in your way to whack him with a sword, I think I'd be paying
some attention to what you are doing.
--
Jasin Zujovic
Reginald Blue
Not that this has any bearing on real life, but, in playing multi-player
games, it's amazing how often someone cuts across your axis of fire, WHILE
YOU'RE FIRING. *grumble*
Marcel Beaudoin
He has never given cover bonus to an enemy's AC when someone with a
reach melee weapon attacks through another person's square (enemy or
ally) to attack someoen. Only with ranged attacks.
Marcel
Jasin Zujovic
I think cover should apply to reach weapons.
(And I still think that if you rule that you hit the cover when you miss
because of cover, "cover" should get his full AC even when shot with a
ranged weapon by an ally. If you're cutting in front of someone
propelling deadly things, you should be paying attention, enemy or
ally.)
--
Jasin Zujovic
Justisaur
wrote:
> Reginald Blue wrote:
> > So, I'm pretty sure I know the answer but...
>
> > Consider this text from the SRD:
>
> Hate it when I hit the wrong key like that...
>
> Text from SRD:
>
> "To determine whether your target has cover from your ranged attack, choose
> a corner of your square. If any line from this corner to any corner of the
> target's square passes through a square or border that blocks line of effect
> or provides cover, or through a square occupied by a creature, the target
> has cover (+4 to AC)."
>
I'm not sure, this might be an old rule but I still use it, the amount
of cover provided is reduced by dex bonuns, so if someone has an 18
dex (+4) and isn't wearing armor that reduces it they provide no
cover.
> The question is, if you miss by the amount specified by Cover, do you hit
> the Cover? I'm presuming the answer is "no", but I am understandably
> curious as to what other people do in their games.
Yes, if you would have hit their AC.
- Justisaur
Jasin Zujovic
> > > So, I'm pretty sure I know the answer but...
> > >
> > > Consider this text from the SRD:
> >
> > Hate it when I hit the wrong key like that...
> >
> > Text from SRD:
> >
> > "To determine whether your target has cover from your ranged attack, choose
> > a corner of your square. If any line from this corner to any corner of the
> > target's square passes through a square or border that blocks line of effect
> > or provides cover, or through a square occupied by a creature, the target
> > has cover (+4 to AC)."
>
> I'm not sure, this might be an old rule but I still use it, the amount
> of cover provided is reduced by dex bonuns, so if someone has an 18
> dex (+4) and isn't wearing armor that reduces it they provide no
> cover.
It's either 3.0 or something from OA. I remember using my naginata
through our monk with no penalty in our OA game.
> > The question is, if you miss by the amount specified by Cover, do you hit
> > the Cover? I'm presuming the answer is "no", but I am understandably
> > curious as to what other people do in their games.
>
> Yes, if you would have hit their AC.
Sure.
--
Jasin Zujovic
Will Green
No. I think it worked that way in 3.0, but not in 3.5. See the DMG
3.5, p. 24, for a *variant* rule that works as described above. But by
the RAW, there's no chance to hit the cover-provider.
-Will
Jim Davies
inscribed:
Open to abuse. AC60 Tank in front of something else. You now have a
4/20 chance of hitting the tank, rather than needing an N20.
If this were changed to "if you would have hit, but the cover bonus to
AC makes you miss, you roll again vs the cover's AC to see if you hit
it", it might make more sense. Still not perfect, though.
--
Jim or Sarah Davies, but probably Jim
D&D and Star Fleet Battles stuff on http://www.axsm89.dsl.pipex.com
becaue pipex's technical support is crap and so http://www.aaargh.org doesn't work.
tussock
> Reginald Blue wrote:
>> So, I'm pretty sure I know the answer but...
>>
>> Consider this text from the SRD:
> The question is, if you miss by the amount specified by Cover, do you hit
> the Cover? I'm presuming the answer is "no", but I am understandably
> curious as to what other people do in their games.
Modelled on personal preference, rather than the rules.
If you hit AC 5-8 (against Medium opponents), your shot perhaps hit
the cover. If it ever matters you roll again to hit it at +0 (with no
range penalties and no auto-hit on a 20).
Basically if you want to know how close you got to a real hit,
targets are AC (size mod+5), plus cover, (dodge+5), insight, luck,
shield, deflection, armour, natural armour, and divine/profane, in that
order.
One could also save some head work and just say 20% of misses
strike the cover, again rerolling at +0.
--
tussock
Aspie at work, sorry in advance.
Jasin Zujovic
> >>> The question is, if you miss by the amount specified by Cover, do you hit
> >>> the Cover? I'm presuming the answer is "no", but I am understandably
> >>> curious as to what other people do in their games.
> >>
> >> Yes, if you would have hit their AC.
> >
> > Sure.
>
> No. I think it worked that way in 3.0, but not in 3.5. See the DMG
> 3.5, p. 24, for a *variant* rule that works as described above. But by
> the RAW, there's no chance to hit the cover-provider.
Ah, I meant "sure, if you use the rule that missing because of cover
means you hit the cover, you have to hit the covers AC to damage them
rather than hitting automatically".
--
Jasin Zujovic
Will Green
>
> Ah, I meant "sure, if you use the rule that missing because of cover
> means you hit the cover, you have to hit the covers AC to damage them
> rather than hitting automatically".
Ah. Right. Ahem. Sorry. :)
-Will
Reginald Blue
> Reginald Blue wrote:
>> Reginald Blue wrote:
>>> So, I'm pretty sure I know the answer but...
>>>
>>> Consider this text from the SRD:
> <Re: cover>
>> The question is, if you miss by the amount specified by Cover, do
>> you hit the Cover? I'm presuming the answer is "no", but I am
>> understandably curious as to what other people do in their games.
>
> Modelled on personal preference, rather than the rules.
>
> If you hit AC 5-8 (against Medium opponents), your shot perhaps
> hit the cover. If it ever matters you roll again to hit it at +0
> (with no range penalties and no auto-hit on a 20).
Interesting... I might add strength to that second one, if applicable (i.e.
throwing a javelin really hard would be bad for the target regardless of
whether it was an intentional or unintentional attack.)
> Basically if you want to know how close you got to a real hit,
> targets are AC (size mod+5), plus cover, (dodge+5), insight, luck,
> shield, deflection, armour, natural armour, and divine/profane, in
> that order.
>
> One could also save some head work and just say 20% of misses
> strike the cover, again rerolling at +0.
That, come to think of it, while less accurate, would make the game flow
better...
Loren Pechtel
<j...@aaargh.NoBleedinSpam.org> wrote:
>On the grave of "Marcel Beaudoin" <marcel....@gmail.com> is
>inscribed:
>
>>On Feb 20, 1:46 pm, "Reginald Blue" <Reginald_B...@hotmail.com> wrote:
>>> The question is, if you miss by the amount specified by Cover, do you hit
>>> the Cover? I'm presuming the answer is "no", but I am understandably
>>> curious as to what other people do in their games.
>>
>>My DM rules that if you would have hit, but the cover bonus to AC
>>makes you miss, you hit the cover.
>
>Open to abuse. AC60 Tank in front of something else. You now have a
>4/20 chance of hitting the tank, rather than needing an N20.
>
>If this were changed to "if you would have hit, but the cover bonus to
>AC makes you miss, you roll again vs the cover's AC to see if you hit
>it", it might make more sense. Still not perfect, though.
I dislike this version.
My take on it:
Take the *SAME* roll and figure it against the cover.
If it hits the cover's current AC then it damages the cover.
If it hits the cover's flat-footed AC but not it's current AC then the
cover evades it, it hits the target normally.
If it doesn't hit the cover's flat-footed AC then it hits the cover's
armor and is harmlessly deflected.
Jasin Zujovic
> >>On Feb 20, 1:46 pm, "Reginald Blue" <Reginald_B...@hotmail.com> wrote:
> >>> The question is, if you miss by the amount specified by Cover, do you hit
> >>> the Cover? I'm presuming the answer is "no", but I am understandably
> >>> curious as to what other people do in their games.
> >>
> >>My DM rules that if you would have hit, but the cover bonus to AC
> >>makes you miss, you hit the cover.
> >
> >Open to abuse. AC60 Tank in front of something else. You now have a
> >4/20 chance of hitting the tank, rather than needing an N20.
> >
> >If this were changed to "if you would have hit, but the cover bonus to
> >AC makes you miss, you roll again vs the cover's AC to see if you hit
> >it", it might make more sense. Still not perfect, though.
>
> I dislike this version.
>
> My take on it:
>
> Take the *SAME* roll and figure it against the cover.
>
> If it hits the cover's current AC then it damages the cover.
>
> If it hits the cover's flat-footed AC but not it's current AC then the
> cover evades it, it hits the target normally.
>
> If it doesn't hit the cover's flat-footed AC then it hits the cover's
> armor and is harmlessly deflected.
Doesn't comparing a single attack roll to that many values strike you as
needlessly complicated?
--
Jasin Zujovic
Ed Chauvin IV
scrawled:
And comparing several attack rolls to that many values isn't?
--
DISCLAIMER : WARNING: RULE # 196 is X-rated in that to calculate L,
use X = [(C2/10)^2], and RULE # 193 which is NOT meant to be read by
kids, since RULE # 187 EXPLAINS homosexuality mathematically, using
modifier G @ 11.
"I always feel left out when someone *else* gets killfiled."
--Terry Austin
Jasin Zujovic
> >> >If this were changed to "if you would have hit, but the cover bonus to
> >> >AC makes you miss, you roll again vs the cover's AC to see if you hit
> >> >it", it might make more sense. Still not perfect, though.
> >>
> >> I dislike this version.
> >>
> >> My take on it:
> >>
> >> Take the *SAME* roll and figure it against the cover.
> >>
> >> If it hits the cover's current AC then it damages the cover.
> >>
> >> If it hits the cover's flat-footed AC but not it's current AC then the
> >> cover evades it, it hits the target normally.
> >>
> >> If it doesn't hit the cover's flat-footed AC then it hits the cover's
> >> armor and is harmlessly deflected.
> >
> >Doesn't comparing a single attack roll to that many values strike you as
> >needlessly complicated?
>
> And comparing several attack rolls to that many values isn't?
I guess that's why they dropped that rule altogether, so you just roll a
single attack vs. the targets AC + 4, and you either hit or miss.
--
Jasin Zujovic
Reginald Blue
> On Wed, 21 Feb 2007 01:26:06 +0000, Jim Davies
> <j...@aaargh.NoBleedinSpam.org> wrote:
>
>> On the grave of "Marcel Beaudoin" <marcel....@gmail.com> is
>> inscribed:
>>
>>> On Feb 20, 1:46 pm, "Reginald Blue" <Reginald_B...@hotmail.com>
>>> wrote:
>>>> The question is, if you miss by the amount specified by Cover, do
>>>> you hit the Cover? I'm presuming the answer is "no", but I am
>>>> understandably curious as to what other people do in their games.
>>>
>>> My DM rules that if you would have hit, but the cover bonus to AC
>>> makes you miss, you hit the cover.
>>
>> Open to abuse. AC60 Tank in front of something else. You now have a
>> 4/20 chance of hitting the tank, rather than needing an N20.
>>
>> If this were changed to "if you would have hit, but the cover bonus
>> to AC makes you miss, you roll again vs the cover's AC to see if you
>> hit it", it might make more sense. Still not perfect, though.
>
> I dislike this version.
>
> My take on it:
>
> Take the *SAME* roll and figure it against the cover.
>
> If it hits the cover's current AC then it damages the cover.
So, my expertise (+20 BAB) in hitting the horrifying monster improves my
ability to accidentally hit my friend Fred who stupidly stepped in front of
me to attack the monster in melee?
That seems nonsensical to me? I'm not aiming at Fred's weak spot, I'm
aiming at the monster's weak spot, and Fred got in the way.
Justin Alexander
Reginald Blue wrote:
> Reginald Blue wrote:
> > So, I'm pretty sure I know the answer but...
> >
> > Consider this text from the SRD:
>
> Hate it when I hit the wrong key like that...
>
> Text from SRD:
>
> "To determine whether your target has cover from your ranged attack, choose
> a corner of your square. If any line from this corner to any corner of the
> target's square passes through a square or border that blocks line of effect
> or provides cover, or through a square occupied by a creature, the target
> has cover (+4 to AC)."
>
> The question is, if you miss by the amount specified by Cover, do you hit
> the Cover? I'm presuming the answer is "no", but I am understandably
> curious as to what other people do in their games.
Huh. I thought that was covered in the rulebook.
(pokes around)
Looks like they yanked it for 3.5. Here's the text from the 3.0 SRD:
"Striking the Cover Instead of a Missed Target
If it ever becomes important to know whether the cover was actually
struck by an incoming attack that misses the intended target, the DM
should determine if the attack roll would have hit the protected
target without the cover. If the attack roll falls within a range low
enough to miss the target with cover but high enough to strike the
target if there had been no cover, the object used for cover was
struck. This can be particularly important to know in cases where a
character uses another character as cover. In such a case, if the
cover is struck and the attack roll exceeds the AC of the covering
character, the covering character takes the damage intended for the
target.
If the covering character has a Dexterity bonus to AC or a dodge
bonus, and this bonus keeps the covering character from being hit,
then the original target is hit instead. The covering character has
dodged out of the way and didn't provide cover after all. A covering
character can choose not to apply his Dexterity bonus to AC and/or his
dodge bonus, if his intent is to try to take the damage in order to
keep the covered character from being hit."
Like a lot of the combat rules, I find that text to be needlessly
complex and confusing. But you can boil down the question of "what did
I actually hit?" in combat with a fairly self-evident decision tree:
1. Check your attack roll against 10 + the target's Dex/dodge
modifier. Would you have hit the target?
NO: You missed completely. YES: Goto step 2.
2. Check you attack roll against 10 + the target's Dex/dodge modifier
+ target's shield bonus. Would you have hit the target?
NO: They blocked with their shield. YES: Goto step 3.
3. Check your attack roll against 10 + the target's Dex/dodge modifier
+ target's armor bonus. Would you have hit the target?
NO: You hit them, but their armor protected them. YES: Goto step 4.
4. Check your attack roll against 10 + the target's Dex/dodge modifier
+ target's armor bonus + cover bonus. Would you have hit the target?
NO: Goto step 5. YES: You hit them.
5. Is the cover being provided by another combatant?
NO: You hit the cover. YES: Goto step 6.
6. Check your attack roll against 10 + the cover's Dex/dodge modifier.
Would you have hit the cover?
NO: The character providing cover can choose to dodge out of the way,
in which case you hit your original target. YES: Goto step 7.
7. Check your attack roll against the total AC of the character
providing cover. Would you have hit them?
NO: Your attack strikes the cover, but causes no damage. YES: You hit
the cover, roll for damage.
Those are the rules as they were written for 3.0.
Now, don't blink, but these rules do provide one little bit of
weirdness: Put Character A in front of Character B. The more armor
that Character B is wearing, the less likely it is that you'll hit
Character A when shooting at Character B. This, of course, makes no
sense.
What you could do is check to see if the character providing cover can
dodge out of the way FIRST. But this creates an even more complicated
rule:
1. Compare your attack roll to 10 + the Dex modifier + the dodge bonus
of the character providing cover. If you succeed, the character
provides cover and the target of the attack gains a cover bonus to AC.
If you fail, the character providing cover can choose to dodge out of
the way of your attack. If they do so, the target of your attack does
not gain a cover bonus to AC.
2. If the character does provide cover for the target, compare your
attack roll to AC 10 + the cover bonus to AC. If you succeed on this
check, your attack has struck the character providing cover. Compare
your attack roll to the total AC of the character providing cover to
see if you have hit them for damage. If you fail on this check,
compare your attack roll to the total AC of the character you're
targeting to determine whether you hit your target.
Here's how you could generalize all this into a simple rule, but one
which would look ridiculous until you thought it through:
If you miss the target of your attack, but would have succeeded
against AC 14, you may have hit the target providing cover. Compare
your attack roll to the total AC of the target providing cover to
determine whether you've hit them for damage.
And this is probably why the rules were eliminated in 3.5: Because,
when you run the numbers, you discover that -- after eliminating the
problems of the 3.0 rule -- the only time you'll hit the character
providing cover is when they have an AC lower than 14. And even with
the 3.0 rule, it only matters in the extremely rare occasion when the
character providing cover has a higher Dex + dodge bonus than the
total AC bonus of the character you're trying to hit. You might
occasionally see this at low levels, but you'll essentially never see
it at high levels.
Justin Alexander
> On Feb 20, 10:46 am, "Reginald Blue" <Reginald_B...@hotmail.com>
> wrote:
> > Reginald Blue wrote:
> > > So, I'm pretty sure I know the answer but...
> >
> > > Consider this text from the SRD:
> >
> > Hate it when I hit the wrong key like that...
> >
> > Text from SRD:
> >
> > "To determine whether your target has cover from your ranged attack, choose
> > a corner of your square. If any line from this corner to any corner of the
> > target's square passes through a square or border that blocks line of effect
> > or provides cover, or through a square occupied by a creature, the target
> > has cover (+4 to AC)."
> >
>
> I'm not sure, this might be an old rule but I still use it, the amount
> of cover provided is reduced by dex bonuns, so if someone has an 18
> dex (+4) and isn't wearing armor that reduces it they provide no
> cover.
That's a nice way of simplifying the "dodging cover" element from the
3.0 rule, but it doesn't answer the "did you hit the cover?" question.
On a tangent: The most assinine special case rule in the game system
has to be the "25% chance you hit the wrong target during a bull rush"
rule. Really? Just the bull rush? Not while they're grappling? And
just a straight-up 25% chance, no matter how skilled you are as a
combatant? Lame, lame, lame.
--
Justin Alexander
http://www.thealexandrian.net
Ed Chauvin IV
scrawled:
>At Thu, 22 Feb 2007 09:45:44 -0600, Ed Chauvin IV wrote:
And what happens when the cover prevents you from hitting your target?
Is the cover struck or not? Where does the missile go?
Jasin Zujovic
> >> >> >If this were changed to "if you would have hit, but the cover bonus to
> >> >> >AC makes you miss, you roll again vs the cover's AC to see if you hit
> >> >> >it", it might make more sense. Still not perfect, though.
> >> >>
> >> >> I dislike this version.
> >> >>
> >> >> My take on it:
> >> >>
> >> >> Take the *SAME* roll and figure it against the cover.
> >> >>
> >> >> If it hits the cover's current AC then it damages the cover.
> >> >>
> >> >> If it hits the cover's flat-footed AC but not it's current AC then the
> >> >> cover evades it, it hits the target normally.
> >> >>
> >> >> If it doesn't hit the cover's flat-footed AC then it hits the cover's
> >> >> armor and is harmlessly deflected.
> >> >
> >> >Doesn't comparing a single attack roll to that many values strike you as
> >> >needlessly complicated?
> >>
> >> And comparing several attack rolls to that many values isn't?
> >
> >I guess that's why they dropped that rule altogether, so you just roll a
> >single attack vs. the targets AC + 4, and you either hit or miss.
>
> And what happens when the cover prevents you from hitting your target?
> Is the cover struck or not? Where does the missile go?
It's handwaved away!
--
Jasin Zujovic
Jasin Zujovic
> > > So, I'm pretty sure I know the answer but...
> > >
> > > Consider this text from the SRD:
> >
> > Hate it when I hit the wrong key like that...
> >
> > Text from SRD:
> >
> > "To determine whether your target has cover from your ranged attack, choose
> > a corner of your square. If any line from this corner to any corner of the
> > target's square passes through a square or border that blocks line of effect
> > or provides cover, or through a square occupied by a creature, the target
> > has cover (+4 to AC)."
> >
> > The question is, if you miss by the amount specified by Cover, do you hit
> > the Cover? I'm presuming the answer is "no", but I am understandably
> > curious as to what other people do in their games.
>
> Huh. I thought that was covered in the rulebook.
>
> (pokes around)
>
> [snip]
>
> And this is probably why the rules were eliminated in 3.5: Because,
> when you run the numbers, you discover that -- after eliminating the
> problems of the 3.0 rule -- the only time you'll hit the character
> providing cover is when they have an AC lower than 14. And even with
> the 3.0 rule, it only matters in the extremely rare occasion when the
> character providing cover has a higher Dex + dodge bonus than the
> total AC bonus of the character you're trying to hit. You might
> occasionally see this at low levels, but you'll essentially never see
> it at high levels.
If rgfd had a reputation system, you'd get it for this. Very nice post.
--
Jasin Zujovic
Justisaur
In more ways than one ;)
- Justisaur
BullHorn
If a creature that is behind cover being attacked with a roll equal to
or higher than his AC, but not high enough once considering his cover,
the cover is HIT -- If the cover is another creature, and it's AC is
higher than the attack roll, the cover is missed and the creature that
was behind the cover is hit. The 'cover' creature can choose not to
apply his Dex and/or Dodge modifiers to AC, if there is actually a
purpose in providing cover, like trying to save a friend, etc.
Justin Alexander
Your summary here is not accurate. The variant rule you cite here is
identical to the 3.0 rule, although it's worded better. The correct
summary runs thus:
1. If you only miss your target because of the cover bonus to AC, you
have hit the object providing cover.
2. If the object providing cover is a creature, compare you attack
roll to their AC to determine if they're hit.
3. If you only miss the creature providing cover because of their Dex
and/or dodge bonus to AC, they can choose to dodge out of the way. If
they do so, the original target of your attack is hit. If they don't
dodge out of the way, they're hit and take damage.
As noted elsewhere in the thread, this means that you're less likely
to hit the wall if the guy standing behind it is wearing plate. But
there's no way to avoid this without introducing even more wackiness.
Some Guy
That's "Deflect Arrows" of course, DOOFUS! ;-)