I believe the item you're talking about is Radiant Virtue. It used to be viable on her, but the item was changed a few patches ago, where it costs more, and doesn't give Ability Haste to everyone anymore. So it is much less desirable as a buy, because of the cost, missing ability haste, and essentially locking yourself out from using Mantra until the big team fight happens. If Karma can build Radiant Virtue, she'd likely just find more success by building Locket of the Iron Solari instead

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