Modeling immunity to non-magical weapons

[Jeminai]

I am planning to run a game and use some old fashioned D&D creatures that have immunity to non-magical weapons and even a few with immunities to any magical weapons without at least a +1 enchantment.

Any ideas on how to build an advantage that grants this in GURPS?

[David Johnston2]

The thing you have ask yourself with effects like this is is what the immunity is intended to represent. Is it because they are actually spirits that can affect the corporeal world? Then do it with Insubstantial or Diffuse. Are they just really tough but magic ignores the toughness? Then Damage Reduction and Regeneration or DR is the way to go.

[Fred Brackin]

Originally Posted by Jeminai

I am planning to run a game and use some old fashioned D&D creatures that have immunity to non-magical weapons and even a few with immunities to any magical weapons without at least a +1 enchantment.

Any ideas on how to build an advantage that grants this in GURPS?

You don't try and do absolute immunity Gurps won't give you a price for that (except infinity).

Instead you settle fro enough DR to be effectively immune to normal weapons in the hands of average humans. DR10 maybe with a "not v. enchanted weapons" Limitation.

[NineDaysDead]

Originally Posted by Jeminai

I am planning to run a game and use some old fashioned D&D creatures that have immunity to non-magical weapons and even a few with immunities to any magical weapons without at least a +1 enchantment.

Any ideas on how to build an advantage that grants this in GURPS?

Is this for PCs or NPCs?

[Varyon]

Ghostdancer explored this some a while back. The advantage in D&D was typically indicated as the wounds closing up instantly, so I'd probably go with a combination of Injury Tolerance: Damage Reduction and Regeneration, both with Bane: Magic -20%.

[Flyndaran]

Everyone and their grandmother has a magic weapon in D&D. I never considered it much of an advantage to anything but animal attacks and natural disasters.

[Andreas]

If you go with the enough DR to negate any attack in the setting approach, you might also want to add a limited version of Injury Tolerance (No Head) since there is a critical hit result for attacks to the head that ignores DR.

[roguebfl]

You could do the Unkillable with the Achilles Heel being Magic (which includes both spells and enchanted weapons)

[ericthered]

In the game 'God Slayers', the trait is represented as such:

Insubstantial (Affects Substantial +100%, no Permeation -50%, Achilles heel -10%, Relexive +40%, Partial Change +50%) [184]

It functions a good deal like infinite DR. The PC's do not seem to find it a particularly good deal, judging by who took it and who didn't. (we had 1 character take it full, one take it with limited uses, despite a massive 1000 point budget). The Achilles heel includes the trait itself and for the game you had to pick something like obsidian, bone, or silver.

I haven't found it unbalancing at all.

I'm aware this might not be raw, but its fairly close.

[Nymdok]

Originally Posted by ericthered

In the game 'God Slayers', the trait is represented as such:

Insubstantial (Affects Substantial +100%, no Permeation -50%, Achilles heel -10%, Relexive +40%, Partial Change +50%) [184]

It functions a good deal like infinite DR. The PC's do not seem to find it a particularly good deal, judging by who took it and who didn't. (we had 1 character take it full, one take it with limited uses, despite a massive 1000 point budget). The Achilles heel includes the trait itself and for the game you had to pick something like obsidian, bone, or silver.

I haven't found it unbalancing at all.

I'm aware this might not be raw, but its fairly close.

This is a handy build as is Ghost Dancers, but

Originally Posted by NineDaysDead

Is this for PCs or NPCs?

This guy has the right of it. As soon as you say 'its an NPC' the discussion then becomes largely academic (unless of course you need a full work up for Ally/Enemy etc).

Remember that you also need to tack down what you mean by 'enchanted' as in GURPS you can seperate the +1 bonus to hit and the +1 Bonus for damage.

Nymdok