While we've been busy datamining new models and tier set changes in this week's Patch 9.2 PTR build, Simaia has shared new findings on Twitter which indicate that additional gender customization may be coming to World of Warcraft. Currently, the only place this index is used is for armor sets which change appearance based on gender — one robe model may be more revealing for females and use a different texture than males, which this index is used to annotate.
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