I'd... not be particularly fond of that one.  I mean, Sam's pretty pitiful solo, yet it would make sense as someone with a +12 Will save that he/she would be pretty badass against psychic possession attacks and fairly powerful in dream world.  That the only representation of that if he/she were attacked tonight were the ability to give the spirit a sex change by kissing it, heal it, or detect that the evil spirit of doom is, indeed, magical.  None of which represents that tremendous force of will.  There needs to be another way to resolve the situation than just direct damage when the characters are already tapped.