the no combat damage property negates the weapons base damage die.
Meaning, the 1d6 or 1d8 or whatever that it does. You still do +x dmg where your str modifier is x.
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However, the no combat dmg property coupled with a damage penalty of -10 or 20 something huge would allow for weapons that would do either no damage (barring extordinary circumstances that well, dont practice hit someone in them) or only 1 dmg per hit. I dont remember if the dmg penalty in conjunction with no combat dmg will round dmg to 1 rather than drop it to 0.
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I agree with this suggestion and do not think that sparring with such weapons (were they available) would be a violation of PvP since there would be no chance of accidental death, barring doing something really stupid. However, the chance of death due to doing something really stupid is always there whether you are sparring or not.
Of course attacking someone that has not agreed to engage you in sparring match would be griefing (especially if it is continued) even though it wouldnt do any dmg, for the same reason following someone around and casting hold person on them every 2 mintues would be (if they werent agreeing to it as a player and it wasnt part of some RP or on a Quest) .. that was meant to be a ridiculously obvious example of griefing, but as soon as I said it I thought of at least a dozen hypothetical quest situations in which a player might cast hold person on another player every 2 minutes.. soo...
the botom line is: Only play with other consenting adults. *nods(
-TV