Obara's text box states:
Obara Sand may be declared as a defender during Power challenges in which you are the defending player, even while kneeling."
I'm pretty certain this means she is eligible to be declared as a defender in Power challenges even though she doesn't have a Power icon, and that she doesn't need to be standing, but since English isn't my first language, I can't be 100% sure whether she needs the icon or not. Does the punctuation (", even while") ensure that the first and second part are separate effects (the second being a "bonus" to the first)?
And in another thread, it was suggested that if Obara was Stealth-ed, this would stop the player from declaring her as a defender; If I had to guess, I'd say that is because the "not eligible" effect of Stealth trumps Obara's ability (to "be eligible"), but I couldn't find it in the rules. Would this be explained via the "Cannot" entry in the RRG?