Supers

[Anaraxes]

Originally Posted by Prince Charon

'Penalties to the attack roll' is how I reflexively think of Passive Defence working

In 3e, Passive Defense added to the value of Active Defense scores, just as DB (Defensive Bonus) does in 4e. Also, the 4e calculation of an Active Defense as something like "3 + skill / 2" shows the 3e lineage. In 4e, the "3" is just a uniform value applied to all defenses in place of the no-longer-existent PD to keep in numbers in the right range and avoid having to redesign the whole combat system just to get rid of PD. The 3e version would have been "PD + skill / 2", where PD was a stat based on your armor type, including shields.

PD was supposed to represent the armor's ability to passively turn a blow (hence the name). So, it worked even if you were unconscious on the ground (to reprise an earlier comment), not just as part of Active Defense rolls. It gave characters a small chance always to avoid damage.

A bonus to the defense is close to the effect of a penalty to the attack roll, but they're not quite the same thing. Defense isn't a Contest -- MoS doesn't matter, you only have to succeed at the defense roll.

(This is why Deceptive Attack is important; it's not a bonus to your attack, it's a penalty to the target's defense, which in typical situations is more effective than an attack bonus of the same size. Note the 2:1 exchange rate for a balanced DA: -2 to attack buys -1 to defense. If you wanted DB to be an attack penalty rather than a defense bonus, you'd probably have to double the values.)