Gargoyle Trap "Immune to Cold" even with cold sunder

I have a Renewed Cold Rupture on my frostmaiden bowazon, and Gargoyle Traps in Hell Catacombs (TZ, Cold Enchanted) are still showing as "Immune to Cold". How is this possible?

It's possible because the way Sunder charms work is that they have a cap of how high of a immunity they can break. The maximum resistance that a sunder charm can break is 399, and Gargoyle Traps actually have 1000 (!) cold resistance.

Quoting @DarkMaster from a post over at the Blizzard forums:

DarkMaster wrote:

The way sunders work is they have a stat called “pierce-immunity-x” (x being the specified immunity) set at 300, as seen in uniqueitems.txt. “pierce-immunity-x” works by reducing a monsters resistance until it reaches a floor of 95, so sunder charms can break the immunity of any monster up to 399 resistance (399 - 300 = 99), 400+ is unbreakable.

https://us.forums.blizzard.com/en/d2r/t ... /157078/10

same for poison immune catapults and doors in a5 i assume? and fire immune cannons in a2 if Memory serves

ShadowHeart wrote: 1 day ago

It's possible because the way Sunder charms work is that they have a cap of how high of a immunity they can break. The maximum resistance that a sunder charm can break is 399, and Gargoyle Traps actually have 1000 (!) cold resistance.

Correct! Pavke did an analysis for physical immunes: https://www.reddit.com/r/diablo2/commen ... is_bugged/

Sunder charms have a stat called pierce-immunity-physical. The value of pierce-immunity-physical is set at 300. Pierce-immunity-physical works by reducing the monster's physical resistance by -300, until it reaches a floor of 95 physical res. Sunder charms can break the immunity of monsters that have up to 399 resistance. Monsters with 400 or more resistance are unbreakable by one Sunder charm. If you want to break those immunities you have to stack Sunder charms.

The same seems to apply to other elements as well. All the Sunder charms have properties pierce-immunity-x (pierce-immunity-cold, pierce-immunity-fire, pierce-immunity-light, pierce-immunity-poison, pierce-immunity-damage, pierce-immunity-magic) with value 300 (to be exact, a range of 300-300).

The last sentence is important:

If you want to break those immunities you have to stack Sunder charms.

So, stacking Sunders of the same element is apparently not pointless? @Spider-Dan, maybe you can test it with multiple cold Sunders?

ganseng wrote: 18 hours ago

same for poison immune catapults and doors in a5 i assume? and fire immune cannons in a2 if Memory serves

Yes, there's a number of "enemies" with resistances that can't be broken with a sunder charm;
- Act 1 Gargoyle Trap (1000% cold resistance)
- Act 2 Fire Tower (1000% poison resistance)
- Act 2 Lightning Spire (1000% poison resistance)
- Act 5 Barricade Door (1000% poison resistance)
- Act 5 Barricade Wall (1000% poison resistance)
- Act 5 Barricade Tower (1000% poison resistance)
- Act 5 Prison Door (1000% poison resistance)
- Act 5 Catapult (1000% poison resistance)

Trang Oul wrote: 17 hours ago

So, stacking Sunders of the same element is apparently not pointless?

Yeah, apparently you need 4 Cold Rupture in your inventory to break the immunity of a Gargoyle Trap This pretty much ensures you have -100 Cold Resistance though.

I'll just use Strafe on gargoyle traps rather than trying to stack 4 cold sunders, lol