thank you for trying to explain it, but as it wasn’t all that clear to me, I searched a lets play on youtube where a player got blabbed by an acid attack.
lets player gets hit by an post patch acid attack
he gets hit at approx 23-24 minutes into the video by a unspotted acid chiron.
now his sniper gets hit for 100 points of acid and as he checks the armor of 5 bodyparts are gone and the acid has been reduced to 10 on these bodyparts. none of the bodyparts had exactly 20 armor on them and the first tick did no HP damage atoll. this indicates that acid can only damage HP or armor, but not both.
as the battle progresses on the start of the next turn the assault (that got hit for a total of 80 on 4 bodyparts) takes a total of 40 HP damage, this means the acid damage stacks as it deals 10 damage per limb it was still on
And the stacking is probably the main reason peoples troops get instantly deleted once hit by multiple acid blobs at once (20 on 4 is survivable…but when you get hit for 40 or more on 4+ limbs HP melts at an insane speed), it should not stack per limb…but deal damage to the HP pool equal to the largest amount of damage dealt to any limb…like burn damage does.
I think the way acid damage stacks is unintentional, so I really hope they fix this quickly.