I think the shadowcaster is fine, and I'm looking forwards to playing one soon.
My plan is, up to level 12,
Eyes of Shadow path
Shutters and Clouds path
Dark Reflections path
Bolster, Warp Spell, and Echo Spell.
Past level 12, I'll either go with Heart and Soul for coolness (path focus and greater path focus augmented), or Ebon Walls because it has both fort and will saves. I'll pick up Shadow Calling either way because it doesn't have saving throws, and I won't need path focus to power it up. My last few mysteries will either be for more castings of my best 9th level mysteries, or for more warp spells. I'm not sure yet.
For feats, I'll pick up Still Mystery, Shadow Reflections (book isn't with me, the 50% miss chance for attacks of opportunity), and Path Focus and Greater Path Focus for Dark Reflections. At level 13, I'll use my bonus feat for Favored Mystery: Shadow Evocation, Greater. I'm looking forwards to shadow evocation forcecages that ignore SR and have a 60% chance of working even if the target makes its save.
At low levels, the plan is to use my mysteries as per a normal caster, but with a backup plan of flanking and demoralizing with intimidate.
I personally think the power level is just fine. I think a lot of people feel it is weak because they devalue defensive options and overvalue offensive abilities. The shadowcasters defenses are great. So many mysteries give concealment or otherwise permit the use of hide checks, and since the Shadowcaster can wear armor (still mystery removes arcane spell failure), they can wear Shadowed Shadowsilk armor, meaning their hide checks will be well nigh unbeatable, giving them a sort of permanent invisibility.
I'm happy with the class and the system. I don't think its at the high end of the power curve, but I think its on there at a respectable point, and that it is worth playing.
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Editted to add:
There are a few things on my wish list as far as the Shadowcaster is concerned, and since Mouseferatu is here, I might as well say them.
Black Fire is reflex negates? That's sad, it makes it almost unusable at higher levels. Reflex Half would have been a better call, in my opinion.
Echo Spell is fun, but it would have been phenomenal if, instead of being limited to 4th level spells, it was limited to spells of, say, 2 levels lower than the highest level mystery you can cast. Then at higher levels it would still be useful in combat, instead of just for echoing your own cleric's healing and such.
I wish a lot of the lower level spells with "will negates" had partial effects on successful saves. Since you can't drop those mysteries in favor of other spells like a wizard would, you need to count on them being saved against quite frequently. A mystery like Killing Shadows is fine with will half even at high levels because you can easily maximize your apprentice mysteries at that point, and even with a save for half, its still 40 damage in an area of effect. Afraid of the Dark is similar. Shadow Vision, on the other hand, seems destined to fall into disuse at high levels, which is sad given how few mysteries you know. If instead of will negates it was will save for half penalty and partial concealment, it would be worth using. Its not such a big deal for higher level spells, but for lower level ones, this would be a nice change.
Final thought: the one change I'd make if I could only make one change, total, would be that if a mystery grows with caster level, but reaches a cap, Path Focus would increase that cap by one level. So a path focused Curtain of Shadows would max out at 16d6.
Really, this is nitpicking. Overall, I like Shadowmagic quite a lot. But what the heck, you're here, so I figured I'd tell you my thoughts.
Thanks.
I'm as curious as anyone to see what people think of the shadowcaster in play. While it's far from the only class I've ever designed, it is the only one I've designed to date that was intended to operate on a brand new system of magic and powers. If it's flawed, I want to know, so I can do better next time.
