Weapon Traits: Help.

[Bublitz]

I dont get it how the weapon trait FORCEFUL works, can anyone enlight me plz?

[When you attack with it more than once on
your turn, the second attack adds a circumstance bonus to
damage equal to the number of weapon damage dice, and each
subsequent attack adds a circumstance bonus to damage equal
to double the number of weapon damage dice.]

the number of weapon dice, is it the damage dice? i mean, a 1d6 weapon with forcefull would give you +6 damage? the next attack +2?

or is it the number of dice? (since is 1d6, so +1... and then +2), if so does Sneak attack in this matter counts as dice for the forceful effect? Therefore adding plus 2 and plus 4 (with sneak attack +1d6 at lv 1-4).

This also aples to Charge, that also works with "number of damage dice"

[Niels Christensen]

The number of dice forceful refers to is most often from magic runes adding more weapon dice and a few abilities with power attack. So with a base forceful weapon your second attack with it on the turn would add +1 damage and any more would add +2. If you instead have a +3 magic weapon for 4 damage dice, your 2nd attack with it would gain a +4 damage and any subsequent attacks would gain +8 damage.

Trying some napkin math, without abilities like haste and agile, it is close to but generally always weaker than a dice step (1d12>1d10 forceful), and abilities like attacks of opportunity favor a dice step over forceful even more.

[Dante Doom]

COUNTING WEAPON DAMAGE DICE

Effects based on a weapon’s number of damage dice (such as charge or forceful) include only the weapon’s damage die plus any extra dice for a magic weapon. They don’t count additional dice from abilities, critical specialization effects, property runes, weapon traits, or the like. On a critical hit, you double this bonus only once; you don’t double it again due to the number of damage dice increasing.