ignores targets defense?

[trashX]

Im not sure if this is correct but the higher someones defense is the higher my AR has to be to hit them, does this mean that if I have a weapon that ignores targets defense I dont need any AR?
If this is true does it work in PvP as well?

[theheft]

Nope, ignore target defence does not work in PVP despite 90% of b.net believing it does!

-% target defence does work though, although its reduced by half I believe.

[trashX]

so a smiter is the only one huh? oh well go figure

[dainbramage]

Guided arrow's 'always hits' also works.

[crawlingdeadman]

what about charged strike and all the other zon light attacks, pretty sure they do as well.

[theBanger]

Chance to Hit

100 * AR / (AR + DR) * 2 * alvl / (alvl + dlvl)
AR = Attack Rating; alvl = Level of Attacker; dlvl = Level of Defender; DR = Defense Rating

Note: Attacks will never have less than 5% chance to hit nor more than 95% chance to hit.

Final chance to hit is truncated.

Example

I have an AR of 10,000. I am lvl85 (attacker) and the Defender is lvl90 with a defense of 5000

= 100 * AR / (AR + DR) * 2 * alvl / (alvl + dlvl)
= 100 * 10000/ (10000 + 5000) * 2 * 85/ ( 85 + 90)
= 1000000/(10000 + 5000) * 2 * 85/(85 + 90)
= 1000000/(15000) * 2 * 85/(175)
= 1000000/(15000) * 2 * 85/(175)
= 66.667 * 2 * 85/175
= 133.333 * 85/175
= 11333.333/175
= 64.761% chance to hit.

Base Attack Rating

(Your attack rating without +AR or +Ar% from equipment, charms or skills)

= (Dex * 5) - 35 + ClassBonus

The ClassBonus is:

20 for Barbarians and Paladins
15 for Assassins
5 for Amazons and Druids
-10 for Necromancers
-15 for Sorceresses

Example

Any lvl Necromancer with 200 Dex.

= (Dex * 5) - 35 + ClassBonus
= (200 * 5) - 35 + (-10)
= (1000) - 35 + (-10)
= 965 + (-10)
= 955AR
strategy.diabloii.net (http://strategy.diabloii.net/news.php?id=551#Chance%20to%20hit)
Just ignores targets defense alone won't guarantee you a successful hit, you also need to factor in your level and attack rating. Also, I believe block will still effect you fully, even if you ignore your opponents defense. I'm 99.9% sure that the only effect that can lower an opponents chance to block besides your level and their dexterity is concentration aura ( 20% chance at an uninterrupted hit).
PvM ofc, ITD doesn't work in PvP