Because people won't stop talking about it

1d8 hooks involving the reason people will suddenly think it's a good idea to stare at the sun. 

  1. The village fool has burned out their retinas by staring at the eclipse. He was given a "magical" pair of glasses by a local wizard, and was told he could view the celestial event safely. Turns out is was just a pair of smoked glass. If confronted, the wizard finds this hilarious and congratulates himself for the wonderful joke. He refuses to return the money, or fix the situation. 
  2. My man who has successfully hidden his lycanthropy for several years is sent berserk and super empowered during the eclipse. He's probably in town when this happens. 
  3. A strange and peculiar plant is found in the forest, and replanted by the town herbalist, who later sells clippings. This plant, and the clippings, are sentient, carnivorous, and evil; all facts the herbalist was trying to keep secret. 
  4. The ancient snake god has returned to the world and is LITERALLY eating the sun. Good luck with that one. 
  5. The celestial event interferes with a wizard's summon ritual. The wizard had no knowledge of the eclipse, but now things from beyond the collected realities are spilling forth from the portal in the sky. 
  6. Turns out the town is cursed! Due to some Incident in the past, the town only appears in this reality during the eclipse, before disappearing again, along with everything in it. "But eclipses don't last that long!" Really? You'll accept magic, but not the fact the moon is just a little more lazy and takes just a little longer to get across the sky?
  7. The eldritch light of the eclipse reveals several of the town's people to be lizardmen in disguise, including at least 1d4 town officials. What do they want? How do the heroes stop them? Maybe the Sasquatch in the nearby forest can help.
  8. A wizard's unattended telescope has accidently focused and entrapped some eclipse light in a bottle. The wizard knows nothing of this, having been drunk for sometime. Since then, the country side has had the same dream, night after night: a voice demanding the return of the starchild and a nightly count down. Last night '1 cycle' remained. What happens at zero? Who is coming? Doom and Starmen, I bet.

Magic and Sanity

Sanity Based Magicking 

The following system assumes the usage of Item Quality, that being a dice value assigned to a consumable item, which is tested on usage. Given a roll of 1-3, the quality lessens to the next step down, thus representing the entropy of the item. For reference the steps are d20>d12>d10>d8>d6>d4. I wish there was a step between d12 and d20, but there ain’t and it's the best I got. Maybe one day the special DCC dice. Maybe. But not yet.

Either way, magic users get a new item: Sanity. The item doesn't take up an inventory slot and can't be traded in a mundane manner. Usually. It can sure as hell degrade, though. The item starts at a quality of d20, and most people you meet should be assumed to be at this rating.

Magic, the way the class reckons, works based in the way the user assumes, and is a reflection of what the user thinks is able to be true. The more your cast, the more you're able to believe is true. However, this thinking isn't natural and is therefore a stress on one’s mentality, occasionally giving way to breaking and insanity. Though, it also “gifts” greater power. Mechanically, this translates to a Wisdom penalty but access to higher level spells.

Highest Spell Level
Wisdom Mod
Most people are at this rating normally
Wizard Sight is constant this level and below

Further, a decrease in sanity is outwardly manifested through delusions. At creation, generate five of them and list them somewhere. The first should be something small - a minor phobia, perhaps. The final should be substainial, a held paradoxical truth about reality possibly. “Fire is actually cold, it is the cold that burns” or some such nonsense. When your sanity first deteriorates, take the first Delusion. When again, take the next. Should your sanity heal, lose the Delusions in a “last in, first out” manner.

As suggested, unlike most items, sanity can repair itself naturally, at a rate of 1 ‘side’ per week of no magic usage; meaning between d4 and d6 takes two weeks, and d12 to d20 takes eight weeks. If locked in an asylum, let's go ahead and say 4 sides per week. Most magic users sit at d12 because of this, giving the stereotype that magicians are weird some truth. Other ways of repair include potions and/or trading. Or outright theft.

Learning Spells
No change from the system your using, I imagine. Save that you can learn any level of spell at any time; just can't access it until the Sanity level is met.

Casting Spells
Casting magic on the system is fairly straight forward: declare the spell you're working, then make an Intelligence check based on your Intelligence attribute modified by the spell level (add if roll over, subtract if roll under). Should you pass, the spell functions. Should you fail, make a Sanity check to see what form the corrupted magic takes. The tables listed suggest a roll under; just flip the numbers if using roll over.
Roll Failure Effect
20 Corruption + Major
19-11 Major
10-5 Standard
4 Minor
3-1 Success (but with meaningless quirk)

Yep, that's right. Still a chance to succeed even if you fail. The chance becomes more probable as you get more crazy

So what happens when you lose Sanity completely?
Ah, yes, that's the question, isn't it? Well, obviously, your insane. You're basically a witless animal with a head full of confusing arcane knowledge, possibly scared, certainly confused, and every spell you cast does so successfully. In short: hand your character sheet to the GM and hope folks can subdue you peacefully. And find a reputable asylum. Maybe it can be fixed, maybe it can't.

You mentioned trading?
I did. Through a complicated ritual, with expensive reagents, the magic user can ‘distill’ another's Sanity out of their body, into a physical representation. The magician can then ingest this item and, after acclimating to the new Sanity, vomit forth their old Sanity to be placed in the original subject. Or not. May you leave them insane. Should the spare Sanity not be ingested within its Quality die worth of hours, it will evaporate into the aether.

Should you want to repair your old Sanity, simply place it into the original target and let them rest for the time period. Yes, this does imply professional lunatics. Though, your own Sanity just feels better. Like wearing old pants.

What about the potions?
Think of them like Pickled Sanity, operating like the trading above, but without vomiting the old one up. It just is that one now.

What about the rest of the class?
What about it? This is largely replacing the "Spells per Day" portion of the class. Everything else should function normally. Unless it doesn't. Then I'll give a refund, if you still have your receipt.

Why would anyone want to play this?
Hell if I know. Though I, myself, enjoy the gambling sort of classes on occasion. Big risk, big reward. Gonna have to sucker someone in to play testing this. And shoot, if'n it doesn't work, maybe it'll at least give someone some idea for something else.