My Trapsin Lightning Sentry Build:

CM PB
Spirit
Griffon + Ancients jewel -10
Enigma
Arach
Horazon Gloves + Boots
Torch + Anni
GC + SC

CTA + Spirit
Holy Freeze Merc + Infinity + Fort + Andy.

Questions:
- I'm not sure between 1x or 2x Opalvein ring (with +5light dmg). The amulet will be 2sin/10-20fcr/stats depending on the ring. I put the build on Maxroll and when I have 2x Opalvein ring, my Lightning Sentry dmg is LOWER then 1x Soj + 1x Opavlein ring. Why? +5light dmg is worse than +1 skill?
-Also, my Lightning Sentry dmg is LOWER if I put -10light Renewed vs. +15light renewed... Why?

Is Maxroll calculator doing something wrong with trap dmg? Blizzard fixed the +dmg / -dmg on trap couple years ago.

Thank!

This post was edited by Xshoot on Jul 6 2026 08:30am

Do I have to select a specific "Monster" to see the real impact of -res?

By default maxroll is showing dmg against a target dummy with 0 res.
Your infinity already brings it down to -85, then only the first -15res from your gear will show a dmg increase in the calculation tabs.
Just switch to other targets, for example a light immune or a high light res target, because those are the targets you want to optimize your dmg against.

Ah yeah. I see. Do you have any "Target recommendation" I should use when ever I have to test the dmg output? I might have to change it when the build use another -res type.

I checked online and Im not sure how to read it.

Thank a lot!

I made some testing with a "Terror Zone/Player1/Normal/Chaos Sanctuary/Storm Caster" monster.

The first build use +15light dmg Renewed.
The second build use -10light Renewed.

Why the first build win? I'm confuse... Like I said, I always tough -res is the king.

BUILD 1


BUILD 2


This post was edited by Xshoot on Jul 8 2026 06:42pm

They're pretty much equal ;P

I'll explain it with simple maths...

Against a target with 0 res, while you have 0 +%dmg and 0 -%res, increasing either of those value is equal.
A 1:1 ratio.
ex:
you have 100 base dmg
if you increase it by 10% you deal 110 dmg against a target with 0 res
if your target has minus 10 res, you also get the same increase, 110 final dmg

Simple, right?

Now, this 1:1 ratio is switching in favour of the value you have the least of against a target with 0 res.
ex:
you have 100 base dmg, your build already has +10% dmg and no -res.
so you deal 110 dmg against a target with 0 res
so now, what's best?
if you get another +10% dmg, you deal 120 dmg
but if you get -10res instead?
now you deal 110 * 1.1 = 121 dmg

Still simple, right?
Keep following, the logic translates in the following explanation...

You have 100 base dmg, and you already have le's say +30% dmg, so you deal 130 dmg
but now, your target has 95 res (sundered)
you already have 35+30+17= 82 light pen
so your target is at 13 res
So at this point, what's better?
Getting an extra -10 or +15?
With -10, your target is at 3res -> 130 * 0.97 = 126.1
With +15, your dmg is now 145 -> 145 * 0.87 = 126.15

Close enough, but +15 won, like in your case.
But what if we tale the same numbers but just change the initial value of +% dmg you had from 30 to 40?
With -10, your target is at 3res -> 140 * 0.97 = 135.8
With +15, your dmg is now 155 -> 155 * 0.87 = 134.85

Now the situation has reversed

Was it enough to help you understand?
It's all about balance!