Cursed Magic Items

[astromath]

Is there any way to add a penalty instead of a bonus to a magic item? Let's say I want a cursed Longsword -1 (instead of a +1). How can this be done since the Bonus box only allows positive values.

[HoratioDrank]

I was able to put a negative modifier in the Bonus box of a magic item. I tested it and it confers -2 to both attack and damage rolls (I put -2 in the bonus box).

[astromath]

I see my problem. I expected the minus sign to show up by erasing the value already there. When it didn't I did not go any further. I just assumed it could only take positive values. My bad.

[HoratioDrank]

No worries. I'm pretty sure we all have those kind of ditzy moments from time to time. I'm glad you got it worked out.

[Zacchaeus]

I can't test this but you may be able to get FG to pick this up automatically if you include the line 'you get a -1 bonus to attack and damage rolls with this weapon' in the weapon description.