A Disadvantage to go with your advantage?

[Fatespinner]

So, in the Core book, the following is listed under "Energy Immunity and Vulnerability."

PRD wrote:

A creature with energy immunity never takes damage from that energy type. If a creature has fire immunity, it also has vulnerability to cold. If a creature has cold immunity, it also has vulnerability to fire. Vulnerability means the creature takes half again as much (+50%) damage as normal from that energy type, regardless of whether a saving throw is allowed or if the save is a success or failure.

Does this mean that sorcerers and wizards, with some of their capstone abilities granting immunity to some energy types, also gain this vulnerability? It seems counter-intuitive, but that is the way the rules appear to be written.

[Liquidsabre]

Thats a good question. It does appear to follow by the rules. Hopefully Elemental Body (and others) will be clarified that this is not the case!

[Xaaon of Xen'Drik]

That would be a terrible capstone ability then.

[The Grandfather]

I expect the beastiary will clarify that.

The immunity/vulnerability issue makes sense for creatures of an elemental/energy sub-type. For a standard race sorcerer/wizard, who does not undergo a physical change, not so much.

However, if the spellcaster aquires the immunity as part of a physical transformation/metamorphosis, then the vulnerability, should without any doubt play in. The disadvantage is not so bad, considering that these high level casters can make themselves immune to their vulnerable element with relative ease.

[Neithan]

The quoted lines are wrong. A creature with the fire subtype that is invulnerable to fire is also always vulnerable to cold.
But it does not make any sense for all creatures that are invulnerable to fire. I think it's probably an oversight by the writer.

[Spacelard]

Fatespinner wrote:

So, in the Core book, the following is listed under "Energy Immunity and Vulnerability."

PRD wrote:

A creature with energy immunity never takes damage from that energy type. If a creature has fire immunity, it also has vulnerability to cold. If a creature has cold immunity, it also has vulnerability to fire. Vulnerability means the creature takes half again as much (+50%) damage as normal from that energy type, regardless of whether a saving throw is allowed or if the save is a success or failure.

Does this mean that sorcerers and wizards, with some of their capstone abilities granting immunity to some energy types, also gain this vulnerability? It seems counter-intuitive, but that is the way the rules appear to be written.

Or if under the influence of a Resist Energy spell or magic item?

I would say not.