I wasn't sure if this should go here or in Advice, but this place seemed more appropriate. Here goes...
I'm trying to make a variant raven for my campaign world, one with connections to shadows (it's a native to a plane that's a weird kind of Plane of Shadow/Fairyland hybrid.) I'm basically trying to bump a CR 1/6 raven up to around CR 1/3 (or some variation that would make five or six of them be roughly worth the XP of a CR 2 encounter.)
The most notable feature is that these "Dusk Ravens" carry a fast-acting curse/disease that I'm calling Diredusk until I can come up with a better name. If a player is scratched by a Raven, they need to make a DC 13 Fortitude save to avoid contracting the disease. The disease contracts within 1d3 hours and once it sets in it requires a save every hour or else 1d8 points of Charisma damage happen as the figure's natural colorations grow grayer and muted. At 0 hit points, they're in a coma-like sleepwalk. The disease is cured when a player makes two consecutive saves, or drinks a dose of holy water (assuming a reasonable knowledge check is rolled for the players to know that.) Ultimately, the disease is the magical curse equivalent of a 24 hour flu, since the players can cure themselves even after they hit to zero since they still roll saves every hour (though no further damage can happen.) If cured at 0, the player would just fall into a regular sleep until they regain at least one point of Charisma.
The Dusk Ravens also have an affinity for shadows. They have a supernatural ability that mimics the 20% miss chance of the Blur spell whenever they're in any light other than bright light as the shadows help to drape them in darkness. Unlike Blur, this ability fails in the presence of almost any effort to pierce the shadows. So, a lantern or torch or candle held in the off-hand, the low-light vision of an elf as long as it's reasonably close, darkvision, wearing a pendant someone cast Light upon, a Sunlight spell going off nearby, etc.
One thing that I'm not quite sure about is if the disease is transferable by regular rules due to the Raven's very low damage. 1d3-4 points of damage is something that I've usually just assumed meant "Minimum 1 damage" but I don't know any actual rule that says damage is always reduced to 1. I've heard that if damage is at 0 hit points (like through damage reduction) no special attacks based on the main attack is confered. So basically I'm not sure if they'd actually deal damage, or if I'd just hand wave it is as painful scratches that confer the disease.
The illness itself is admittedly very fast acting, but I'm hoping the speed of it will also translate to quick healing (lotsa travel time for the adventurers through this forest). For story purposes I'm hoping the players get some experience with this particular illness before moving on to the rest of their Halloween adventure.
The Blur effect is largely flavor text, only really a problem for creatures who dono't have either low-light vision or darkvision. Still, if the party rolls nothing but humans who carry things in both hands, it might cause some issues.
Anyway, thoughts? Criticisms? If I should make it tougher/weaker for my "six of them for CR 2" I'd love to hear suggestions. And, of course, I'd settle for "CR 2 for this one controlled scenario but maybe not elsewhere."
Anyway, thanks in advance.