[CUSTOM] How to force NMs to resist spells and effects

[Freetate]

I want to weaken the magic, which lua will be modified so that sleep and bind cannot successfully cast spells on NM or mob, or modify NM alone so that it cannot be sleep or bind

How to modify if you want to do this

[zach2good]

If you want to change how magic works, scripts/globals/magic.lua is a good place to look:

Using Bind and Sleep as examples:
https://github.com/LandSandBoat/server/blob/base/scripts/globals/spells/bind.lua
https://github.com/LandSandBoat/server/blob/base/scripts/globals/spells/sleep.lua

    local params = {}
    params.diff = dINT
    params.skillType = xi.skill.ENFEEBLING_MAGIC
    params.bonus = 0
    params.effect = xi.effect.SLEEP_I
    local resist = applyResistanceEffect(caster, target, spell, params)

    if resist >= 0.5 then
        if target:addStatusEffect(params.effect, 1, 0, duration * resist) then
            spell:setMsg(xi.msg.basic.MAGIC_ENFEEB_IS)
        else
            spell:setMsg(xi.msg.basic.MAGIC_NO_EFFECT)
        end
    else
        spell:setMsg(xi.msg.basic.MAGIC_RESIST)
    end

applyResistanceEffect looks useful:
https://github.com/LandSandBoat/server/blob/base/scripts/globals/magic.lua#L502

It looks like returning 0 out of here would force a resist, so adding this to the top of function applyResistanceEffect(caster, target, spell, params):

if target:isNM() then
     return 0
end

[Freetate]

After learning, it should be very useful, but what if I just want to change the magic resistance of a few NMs? Which file should be modified？

[Freetate]

---

-- Spell: Sleep

require("scripts/globals/magic")
require("scripts/globals/msg")
require("scripts/globals/status")

local spell_object = {}

spell_object.onMagicCastingCheck = function(caster, target, spell)
return 0
end

spell_object.onSpellCast = function(caster, target, spell)
local dINT = caster:getStat(xi.mod.INT) - target:getStat(xi.mod.INT)

local duration = calculateDuration(60, spell:getSkillType(), spell:getSpellGroup(), caster, target)

local params = {}
params.diff = dINT
params.skillType = xi.skill.ENFEEBLING_MAGIC
params.bonus = 0
params.effect = xi.effect.SLEEP_I
local resist = applyResistanceEffect(caster, target, spell, params)

if target:isNM() then
 return 0

end

if resist >= 0.5 then
    if target:addStatusEffect(params.effect, 1, 0, duration * resist) then
        spell:setMsg(xi.msg.basic.MAGIC_ENFEEB_IS)
    else
        spell:setMsg(xi.msg.basic.MAGIC_NO_EFFECT)
    end
else
    spell:setMsg(xi.msg.basic.MAGIC_RESIST)
end

return params.effect

end

return spell_object

Please take a look to see if this modification is correct！！ thank you！！

[TeoTwawki]

Do you want resistance or immunity, or damage reduction?

we have modifiers for resistance to specific things like bind effect (xi.mod.BINDRES) or ice element (and bind counts as ice) but if you say want a mob to heavily resist all magic you'd want magic evasion (or xi,mod.MEVA)

immunity (where bind can NEVER land) is handled as a mask in mob_pools.sql

and for damage reductions one can add magic defense bonus (xi.mod.MDEF) or change magic damage taken amounts (a per element and an all magic type exist, see src\map\modifier.h).

[ShiyoKozuki]

We need "trait" resist enfeeble mods. Aka flat % chance to 1/16(fully) resist. The way we currently do enfeeble resists is just mevasion to that specific enfeeble, which is wrong and doesn't even exist on retail for any monster or item.

[TeoTwawki]

@ShiyoKozuki agreed that we're doinitwrong, have brought this up many times myself. retail has basically multiple things that get called "resistance" and the old team that began dsp applied just one to..everything.. For Freetate's purposes I think he just wants to prevent certain mobs from being slept because they are too easy, so the short term solution for him is immunity.