User blog comment:Bluestripe the Wild/Gray Characters In Redwall/@comment-24350739-20140111223403/@comment-1298206-20140217183240

I wouldn't say Bluefen is evil judging from the little information we have on her. That being said, it's difficult to say one way or another since she had a limited role in the story.

Skan, on the other hand, is most definitely a gray character for intentionally seeking to harm his former comrades.