'Heartless' and 'Resist Fire III' skills appear to contradict each other

[Kevin Coghlan]

The ‘Heartless’ skill in the ‘Death Mastery’ tree claims to make the player vulnerable to fire, while the ‘Resist Fire 3’ skill in the ‘Pyromancy’ tree claims to make the player invulnerable to fire.

As far as I can tell, there is nothing to stop the player from taking both skills, even though they seem to contradict each other.

[Robert Gaines]

I think this is by design. I know I purposely take the fire resistance skills to mitigate the negative aspects of the heartless skill.

[Kevin Coghlan]

@Robert: if the two skills simply added and removed a certain amount of fire resistance, I would understand how one could mitigate the other.

But actually, one of them claims to give invulnerability to fire. Invulnerable is an absolute term; no fire damage whatsoever. Meanwhile the other skill claims to make the player vulnerable to fire. Logically, there is no way for both to be true at the same time.