For the first, maybe in her rage she could kill someone she knows to be a good person — a childhood friend or a mentor, or someone who previously helped her (maybe someone who nursed her back to health after a battle).
Violence is the last refuge of the incompetent.
Impudent Upstart
For the first, another possibility is that her actions cause an innocent person to go through a similar experience to the one she went through, and they end up swearing revenge on her. Seeing their rage and sadness could make her realize that she's not hurting the Big Bad so much as she is just sowing terror without rhyme or reason.
As for the second, I imagine she might simply become more precise in her actions. She might decide to try a less bloody, but more subtle revenge. Something as simple as telling truths they'd rather not be known, letting their own deeds do them in. Maybe she reveals a secret her enemy was keeping from his men, or does something else to manipulate his most trusted friends into betraying or murdering him for her.
Not sure about what she'd do after. That depends on her character.
Nobody wants to be a pawn in the game of life. What they don't realize is the game of life is Minesweeper.
Definitely Not An Assassin In Disguise
![[up]](https://static.tvtropes.org/pmwiki/pub/smiles/arrow_up.png "[up]"){kind=icon}
Hmm... this could be combined with the next post
Ah, the Not So Different path, a classic 
Maybe she were helped by someone, a villager, commoner or something like that, yet continues to act as if they weren't there/matter. Eventually, her action led to the death of them, and their grieving family/friend tries to have revenge, which eventually led to their death at her blade, forcing her to realize that her action have consenquences, direct or not.
For the second one, well, I do imagine her MO as "Find a bad guy related to Big Bad, march up to their whereabouts, kill everyone" 
However, she swore an oath to kill the Big Bad, thus still have to kill him. Maybe she use tactics instead of brute force? (for example, make the Big Bad come to her instead of the other way around)
Hmm.... if I made her still in incomplete Character Development when the story end, would that makes sense? I mean, she still not sure on what to do, and goes on a travel to find a new purpose.
edited 22nd Sep '13 7:47:29 PM by MoodyXander
Its not the Trope that matters in the story, its the execution.
Impudent Upstart
I'd say that sounds like a good strategy. It still lets her fulfill her oath, but in a more intelligent, directed way. Also lets her show off strengths other than killing fools.
I'd say what you've described would be a reasonable way to end the story. I don't think Character Development can ever really be 'complete' anyway, so long as people are living and experiencing things, etc. It sounds like her 'shift' is the focal point of the story anyway, anything after that might just distract from it. Though some hints as to what she might want to do next, now that her revenge are complete, wouldn't be a bad a idea.
Nobody wants to be a pawn in the game of life. What they don't realize is the game of life is Minesweeper.
Definitely Not An Assassin In Disguise
True
Hmmm... there is some supporting protagonists that she encountered, maybe she could go with him/her/them while looking for what to do next?
Its not the Trope that matters in the story, its the execution.
I'm not sure whether this is well written or not, but here it goes.
It's about an exceptionally talented dojo heiress (probably had No Name Given and goes by her alias, or she does have a name of which I still had no idea of) and fiancee to a samurai family. During her wedding day, the Big Bad attacked and slaughtered her family and friend.
She swore revenge on the leader of the band, swearing to kill him with a wakizashi which is chained until then. Her fury and hatred seeps into her sword, turning it red from the blood of those slain by her, and caused it to be perpetually heated. Despite this, she believes (or deluded) that her cause is right, blocking out everything else that might hinders her. Her delusion is so much so that she can't see the changes on her sword. Only when she see the error in her way shall the true form of her blade be revealed to her. The problem is:
1) What or what would cause her to accept that she is dangerously close to She Who Fights Monsters?
2) How would this changes her behavior and MO? (the guy will need to be killed anyway)
3) How would she goes on from there?
And there's also the question on how would she interact with anyone else since anyone affiliated with the Big Bad's band is a Berserk Button yet I haven't determine how she normally interact with others.
This is still a "fresh" concept, so there's a lot of work required starting from the main character. Any help is appreciated.
edited 22nd Sep '13 3:30:09 AM by MoodyXander
Its not the Trope that matters in the story, its the execution.