multiplicative vs. additive.
and precedence, which ones applied first/favoured, order of operations, etc.
sometimes u +add to the base dmg somtimes u * the modified dmg etc
Everything does stack, but when Echo copies Mercy you can’t double damage boost one hero. Like it doesn’t do 30% + 30% = 60%, it stays as 30% even though there is TWO Mercy damage boost beams connected.
Same with Zenyatta, can’t have two discord orbs on 1 hero. But these situations are just kinda specific and only possible with no limits mode or Echo
I was told once there’s some sort of hard cap on how high the damage boosting will go, and that anything beyond that is wasted. I didn’t commit it exactly to memory, but it might be worth looking at the game’s Wiki (if there is one…there probably is) to see if anything is written on it.
Yes you can stack damage boost if you want to try it if you have a mercy and a zen and you are playing pharah if you shot some like let’s say Ana with the rocket and your damage boost and zen discorded the Ana it will one shot her