I just began a campaign with the pre-gen characters from the WotC page, and we can't explain some stats.
One of them is this Drow Rogue STR modifier. As it has STR 8, it should be -1 instead of 0, and I don't understand why.
Could you shed some light on this, please? We're new at this and we'd like to grasp these kinds of details :)
It seems to be a mistake in the file. There is nothing special going on that I can see, so the number is likely just wrong. I don't know of any rule in the game that would be able to change an attribute modifier.
In addition to Erik's answer, I would like to confirm that the mistake is in the (+0) indeed. It could be that the mistake was at the 8 STR instead, but it follows that: 15 Charisma, 14 Dex, 13 Int, 12 Wis, 10 Con and 8 STR give you exactly the standard array. The +2 Dex, +1 Cha from Drow then puts it into 16 Dex, 16 Cha, and finally the +2 ASI from 4th level make it go up to 18 Cha.
That's to say: The attributes are correct - the modifier is not. As mentioned by Erik, neither Rogues, Drows or the magic items listed are able to do anything about the modifier, so it's most likely an error.
