For horde attacks you can use group roll syntax /r {?{number in horde?|3}d20+3}>?{ac of target?} When using group rolls with a single sub roll AND "target number/successes" the modifier gets applied to each roll then compared to the target. This is an exception to how group rolls typically work. The normal way to do advantage on a 1d20 roll would be 2d20k1, trying that on a horde roll won't work since 6d20k3 would keep the best 3 of all 6 rather than the best of each pair. So you'd have to specify each roll individually. An alternate way to mimic advantage is to add a +3 modifier since the average roll on a d20 is (rounded down) 10 but the average roll on d20 with advantage is 13. True advantage for 3 rolls /r {2d20k1 +3, 2d20k1 +3 ,2d20k1 +3}>?{ac of target?} Mimicked advantage for queried rolls /r {?{number in horde?|3}d20 +3[mod] +3[adv]}>?{ac of target?} When it comes to calculating damage automatically we can only use the outcome of a roll once. So doing 1d6+3 for each success cannot be done the way you imagined in your post since it requires the outcome twice. However 1d6+3 can be rethought as 1d9r<3 since both return 4 to 9 with equal probability but with the latter we need only change the number of dice rolled for a damage calculation. At which point we can use a nested roll for the successes as the number of dice. /r [[{?{number in horde?|3}d20 +3[mod] +3[adv]}>?{ac of target?}]]d9r<3 piercing damage taken
