SpikeyFreak said:
IIRC:
quote:
1) Does this mean that an 18 Dex fighter doesn't offer any effective missle cover?
Yep. Miss by 4 becuase of the cover, and your ally has a 4 point dodge bonus to AC, you hit the target.
--Quote Spikey /Quote
There are three important rulings to be taken out of the "Striking Cover Instead of a Missed Target" section on p133 of PHB.
1.
"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, hte object used for cover was struck."
I don't think anyone has a problem with this part of the rule. With respect to a medium creature giving cover to a medium creature, the creature giving cover is hit where the attack roll misses the intended target by 4 or less.
2.
"...if the cover is struck and the attack roll exceeds the AC of the covering creature, the covering creature takes the damage intended for the target."
INOW, the covering creature's Dex bonus is irrelevant in this instance. If the attack roll exceeds its AC, it is hit, 18 Dex or otherwise.
3.
"If the covering creature has a Dexterity bonus to AC or a dodge bonus, and this bonus keeps the covering creature from being hit, then the original creature is hit instead. The covering creature has dodged out of the way, and didn't provide cover."
The question then is, how does one know if a Dex bonus to AC or a dodge bonus has kept the covering creature from being hit? The answer is quite simple. If the creature was missed, but would have been hit if not for the dex/dodge bonus, then he has "dodged out of the way, and didn't provide cover."
To simplify, as I have said previously (though less coherently), if the attack roll equals or exceeds the covering creature's flat-footed AC, but does not equal or exceed his total AC, he has dodged aside, and the original target is hit.
Frex: Herbert the Fighter has Dex 14 and Full Plate. His AC is 10, +2 Dex, +8 Armour = 20. Any attack roll of 19 or 20 would have hit Herbert, if it were not for his dex bonus to AC. Thus, any time that he is acting as cover and is hit because of that, he actually dodges aside on attack rolls of 19 or 20. On a roll of 21 or more, he is hit (see 2 above), and on rolls of 18 or less, he is hit but the blow does not penetrate his armour. (Note - all these scenarios assume that the original roll falls in the range 1 - 4 less than target AC, and thus would normally hit the cover).
I hope that's fairly clear.
I'm sure there will be many House Rules on the matter, but this is how it works by the rules as written.
EDIT: Completely rewrote post to provide a coherent response.