While we see Willow sliding into darkness, I think that it has highlighted another, maybe even more important, witch. While the writers have even stopped referring to Willow as a "wicca," Tara has been coming into her own as the most ethical witch we have seen on BtVS. At first, as a shy nobody, the audience didn't really know much about Tara. All we could see was that she was an extension of of her girlfriend. Like Oz, she did not say much, just happily went about being in a perfect relationship.

Very chic.

Unlike Oz however, her character has seen major developments. Lucky for us, we can see her change into a more vocal, self-assured woman. Instead of playing the part of an extension, she has become more of a conscience for the group. Although "under Willow's spell," she has come about as clear-headed and having a very "fine mind." She is wholly ethical and moral, but not so closed-minded that she can't be swayed by logic.

In Bargaining, she was convinced that it was a good idea to bring Buffy back. However, she has not switched her moral compass, as she still thinks that frivolous magic is wrong and was willing to make her relationship with Willow unstable because of it. She is also very powerful, although she does not show it often. Like the quiet student with hidden depth, she passes both the magical and mundane tests of life with flying colors.

With God himself.

In sum, despite her recurring rather than regular status, Tara will most likely be the character to watch. As the lines between black and white become blurrier and the Scoobies go down the left-hand path for a bit, she will be the one most likely to set things right.