Quick Dragon Question

[Lordrel]

In reading the Red Dragon description in the Monster Manual, it says "Fire Subtype (Ex): fire immunity, double damage from cold except on a successful save"
Now that save...is this for only things that originally get a save, such as a spell, or is it all frost damage, like from a weapon?
Is this a case where they either take none or double, or is it full or double? It's a little unclear as written, and I can't find mention of it elsewhere.

thanks in advance for the clarification.

 

[Velenne]

IIRC, they take double damage from all cold sources. If it allows a save and they succeed, they take half as normal. If they fail, they take double.

 

[AuraSeer]

Now that save...is this for only things that originally get a save, such as a spell, or is it all frost damage, like from a weapon?

Only things that already get a save. If you hit a red dragon with a frost weapon, the frost damage is doubled, and he does not get a save against it.

 

[Drunken_Master]

Only on against a spell that allows a save for half (Usually Reflex save)