Talk:Nightmarish Impact Super Saiyan Broly/@comment-39294106-20190525030414/@comment-28362353-20190525224944

@Horus, "stack" means if "x boost would also be active on top of x boost"

So like if a unit had "ATK +50% at the start of turn" and "ATK +50% when x happens" then both boosts would be active. It can be addition or multiplication. Like stack attack with characters who launch supers that raise ATK. The buff from each super stacks on top of the previous buff, resulting in more damage.