mithral golem destroyed with missile storm
https://www.youtube.com/watch?v=tdf3K5OjAE4

Vixtra easily killed
https://www.youtube.com/watch?v=B9wYYnf_9nY

I've used the tactic of use Mestil's acid sheath, Elemental shield and shapechange to kill this creatures who is immune to magic. But how he can do spell damage to spell immune creatures?

Mithral Golems have 32 Spell Resistance, but that's it. Also just SR of 32.

If they have SR of 32 instead of magic immunity, this explains. I decided to level up red dragon disciple because i was dying so quicly, so my caster level was not enough to breach his resistance... About Mephistopheles, where i can find his status? Because i was forced to use the "shield + acid + shapechange" tactic on him

EDIT : Mordenkainen's disjunction can breach any immunity?

Trading DC just for HP is always a bad idea. For future ref - it you want def as a caster, you get improve combat expertice(+6 AC, and you don't need AB) or if you are a sorc - get Cleric 1 for divine shield. Need 13 str and power attack, but you shield last long. And strong. Big AC >>>>>> Big hp

Well said. You are right for melee users. My plan is to let enemy hit me and then take damage from Mestil's acid sheath and elemental shield, so in order to do damage to magic immune enemies with this strategy, i need take damage, and if he have a +6 weapon, he can bypass my damage reduction(except with epic spells)

im not certain about NWN 2 but in NWN 1, mords reduces SR by about 10 i think. Being a caster in NWN 1 is about reading and understanding the world around you (ie: read the guidebook and wiki). More than any other game i know, being a magic user in NWN is really about -- studying grimoires and thinking-- and being prepared to fight and cast brilliant magic in the heat of combat....

in NWN 1, if you are a smart and knowledgeable magic-user, you can (theoretically) defeat anything. And magicusers have the most spectacular magic. This is why I like pvp. imho, magic users in pvp (even vs other magic users) is the best pvp you can ever have. provided you are smart. (though killing a magic user by using a non-magic user in pvp is also satisfying)

I've head a lot, searched in a lot of forums. Still don't know if this effects will work in a adamantine golem for example or in a demilich ( http://nwn.wikia.com/wiki/Demilich )

PS : The maker is a `customized` demilich.

Trading DC and CL is bad for casters. Melee users are ok with low DC progression and subpar CL, since DC do not required to cast buffs and CL only used against dispell which not everyone have. If you are an offensive caster, you should NOT have CL lower then your character level minus one, max minus two. You can clearly see that on the video, where dedicated spellcasters kill SR enemies with little problems. Thats why for non-gish damaging shields are waste of spell slot

Shapechange is generally bad choise, especially in HotU, where its increadibly easy to get permahaste weapon, which would not be merged into a balor form. As well as balor loosing all other effects from equipment. Best shapeshifter is still, well, shifter. You can try somewhat like druid8/shifter 21/monk1 with around 30 wisdom to see how nerfed balor is when compared to dragonshape(which merge armor, helmet and shield) with 20d10 breath weapon, aura of fear and 40/+6 DR. And if you drop monk and take one more druid, you get 24d10 breath.Shapechange doesn't even work as good "Oh shit" button, since you can timestop which is exactly same level and can be cast after wearing heavy armor(which would be provided by cleric)

A sorc with ICE and Divine shield can get AC similar to a fighter while having high caster level. After that all this junk like shapechange becomes useless, since you can cast in melee range, and ignore that pesky weapon attacks

The majority of spells damage are caped to lv 20, or 25, so yes, you are right in normal game. In epic game, if your max level is 30,i will agree with you but in nwn1 the max level is 40. So a sorcerer 30/RDD 10 will enjoy RDD benefits, immunity to fire(a lot of creatures use , paralyze and sleep also a lot HP, fortitude and will saves.

If the max level is 30, trade caster level and epic spells for this advantages simple won't worth but with the max level 40, is different.

About shapechange, my idea is not use shapechange to deal damage. Is to cast buffs, then shapechange and then let enemy take damage from "counter melee spells" like acid sheath. Druids can get cool spell resistance spells but nothing like Mestil's acid sheath nor Elemental shield and only use this tactic against spell immune creatures.

Also if you like high AC, here is a sorc 18/rdd 10/pale master 12 that can reach AC 116. http://nwn.wikia.com/wiki/Sorcerer_18/_red_dragon_disciple_10/_pale_master_12

He is virtually immune to all melee attacks.

About balor, i only change to dragon for roleplay(i an a rdd), balor provides more health and better DR and Iron golem provides +300 hp.

We are talking about HotU here, right? Companion, which is capped at lvl 25 assuming you get everything and not skiped some quests. I suppose there are a few abusable places where you can get unlimited xp, but that would be slow and actually not fun at all xD So yes, cutting your CL in HotU is bad.

As for lvl 40 - I don't remember any module\companion, that could go that far. Shards - maybe, but shard are kinda different environment(and If I remember correctly that build often banned there). So effective max lvl even with custom content pretty much always even lower then 25 lvl.

P.S. I advice you to check shifter dragon to compare it with shapeshift one. Use some training module for it. Shapeshift one is really, really nerfed version xD

Sands of Fate is a pretty solid module that allows you to reach near lv 40, so if you play SoF then play hotu with the same character...

You are right. The shift spell is an adult red dragon that can't cast fire breach even if you are a red dragon disciple