[Pathfinder]Balancing a Permanent Affliction

[rt_tlp]

Hey guys!

I run a PF campaign that's completely homebrewed and still constantly in progress, and I'm sure all of you are very familiar with this idea so far. However, I have relatively little experience as a DM. (I've only been at it for 6 months or so, with a grand total of like 10 sessions under my belt)

To keep this brief, some of my characters have done something in my world which I feel deserves a permanent affliction being set upon them:

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Arachnophobia: Upon encountering a creature of arachnid origin/appearance, you must make a 10+(1/2 Character Level [Min. 1]) Will save at the start of combat.
If this Will save is failed, the character is Shaken for 1d4 rounds, and must make another Will save at the end of the Shaken effect. On a natural 1, character is Frightened for 1d4 rounds, then must repeat Will save as above. Once the Will save is successful, it does not need to be made again for 1 hour.

So my question to those more experienced than myself is how to balance this. My first main concern is the Will Save DC for the affliction--no matter what value I've set it to it seems to have the issue of either being too harsh or being all but negligible. I want players to keep it in mind, but not define themselves by it. Any tips on that would be greatly appreciated.

My second concern is less severe--my 1hour limit is in place solely to prevent chains of infinite need to make Will saves should the character somehow find herself in a spider's lair. I think 1 hour seems to be a fair way to prevent that.

Thanks in advance!

[Mr.Moron]

The DC should be set by the spider not by the level of the character.

Something like 10 + 1/2 HD of Spider + [Spider's CHA].

This keeps the fear relevant as more advanced challenges come up, but keeps the PCs from freaking out if they run afoul of a daddy long legs.

Depending on the exact nature of scared them, perhaps there could be an increase or decrease to the DC based on the size (or other relevant property).

Example +2 to the DC if the spider is large or larger, or +2 if it's a swarm. or -2 if it's not Red (or lacks some other property in common with what left them so scarred0.

[DracoDei]

Yeah, might want to base it on size only, rather than HD... HD are a nice concept, but theoretically a character shouldn't know that at a glance, so how could it effect their phobia? Lots of ad-hoc modifiers for how scary looking it is... Driders probably get a +4 or something... I dunno...

There are actually rules for phobias somewhere in the SRD, but I don't know how good they are.

[rt_tlp]

Sorry my reply took so long, guys.

I've been toying with the two things thrown out in this thread so far... I like the practicality of the mechanic suggested by Mr. Moron, but Dracodei certainly brings up a valid point that the players wouldn't know the spiders' HD.

That said, I could always make their Will save for them, I suppose.

I'm definitely probably going to apply some ad-hoc modifiers if I see fit. The spiders that caused this phobia were actually tiny, and there were only 3 of them. However, they had a powerful hallucinogenic poison with long-term psychological effects on the survivors of the encounter.