Maybe a Setting Sun/Brilliant Dawn PrC, if only just for the imagery? The two do have a shared theme of debilitating foes that could be interesting.
Mmm, interesting. This is being added to my to-do list. I already have a pun ready and everything.
Well the Unseen Master isn't really sneaky. It hasn't got Hide or Move silently, and doesn't advance sneak attack.
See, I consider the ability to turn invisible and remove yourself from people's memories to be "sneaky." Sneak attack, to me, is not a particularly sneaky thing--it's just a damage boost slapped onto sneaky things that would otherwise not be particularly stellar in combat.
And I was thinking more in the lines of a Base Class. Something to marry rogue wth spellshaping. There is classes that bring to mind, sorcerer, wizard, warblade, Dragonfire Adept, crusader, dragon shaman...but nothing that says rogue.
The difference is that all of these classes--with the exception of warblade and crusader--are actually based somewhat on magic. The rogue isn't. And, as far as warblade and crusader go, I'm assuming you're talking about the spellshape champion and the sublime shaper. The spellshape champion was written in order to allow a basic gish class, and is more based on the duskblade than anything else. Meanwhile, the sublime shaper exists wholly for the purpose of a spellshaping/initiating gish, not to mimic a particular class's feel.
Basically, a spellshaping base class should be based on magic use. Moreover, I'm leery of doing too many melee-based spellshapers--the spellshape champion serves the generic melee purpose, the sublime shaper serves the purpose of combining two very similar systems, and the dragonheart adept exists as one giant reference to the first piece of homebrew that I ever wrote. If we get too far beyond that, we start treading on the toes of the
Tome of Battle. We already have a melee system that functions more or less identically to spellshaping, so why not use that instead?
Finally, I'm just going to officially note that I am intentionally
not replacing every archetype ever with spellshaping. A large part of why I love 3.5 is that classes all work differently. If I then offer an alternative to every single class, all of which function in exactly the same way...well, that just feels silly to me. Doubly so if I'm just tacking on magic to something that is, at heart, not a magic-using archetype.
Plus I don't realy concider shadow hand/devouring shadow combination trite. It seems a natural combination. An awesome combination. Maybe a swordsage shaper who can channel withering touch through his blades?
Thing is, the two shadow-based ability pools, plus sneak attack, is just...it feels overdone. Moreover, if I did end up writing a Devouring Shadow/Shadow Hand base class with sneak attack, there's probably no way that it would feel like rogue. Because I don't like the idea of
another class that just channels magic through its weapon. We already have one of those, and she's doing quite well.
Instead, it would probably be based on unarmed strikes, which would be its only means of delivering a
withering hand attack. As extra damage, though, not channeled like a spellshape champion. The problem then is sneak attack damage, so that would be cut to half progression--ending up at a maximum of 5d6. After that, though, it still needs a handful of token class features, so I'd probably end up stealing some wuxia-style movement ideas--stuff like letting you run along tree branches, across water, and up walls, as well as being able to jump in straight lines. Then, to appease the "sneaky" aspect, it'd probably receive Hide in Plain Sight and Trapfinding.
This is just me spitting into the wind, you understand. As I've said, I'm not actually particularly attached to the idea of writing another meleeshaper base class. That's what
Tome of Battle is for. In fact, the more that I look at the above paragraph, the more that I realize that it would be pretty much unambiguously better if we cut spellshaping entirely, changed it to a full sneak attack progression, and added the Diamond Mind and Setting Sun disciplines.