So tired today the first time the acidcaster (i know I'm late). And it was awesome. Then I asked myself how PISORF interacts with corrosion, since with two adjacent monsters one would get at level1 far more damage then with the normal fireball.
So first the good news. If you knock a monster into another one with PISORF (would think normal knockback also works the same), both get also the corrosion damage
But the damage calculation is really strange:
Used a gnome wizard with a prepped spoon -> so base damage is at 6, 50% base damage from PISORF -> 3 physical PISORF/knockback damage for each monster. With WEYWUT to put two level3 goblin adjacent to each other.
First started with 2 layers of corrosion. And i did 4 damage (i think). So first thought, the corrosion damage gets also halved.
Then used 3 layers, and i would have assumed, that the damage will get rounded down. But i made 5 damage.
Now I'm at 4 layers -> 6 damage
5 layers -> 7 damage
7 layers -> 9 damage
Don't understand the math. It seems that the first layer of corrosion seems to be missing.
Will make a second run and report the damage for only one layer (for this run i started directly with two layers).