My Theory on an up Coming Champion.
So in Zoe's development she was at one point a Fae, a painter(maybe), and a mirror mage.
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I think these concepts could make for a pretty interesting champion. A cold possibly emotionless Fae who is obsessed with symmetry, geometric shapes, and crystals, who bends reality for their art. Maybe the crystals could be the source of the Glade's magic, maybe they even sucked the magic from the Glade into the crystals, only leaving Pix with Fae magic. They could act as an opposing force to Lulu and Pix's emotional and carefree magic.
Much like Sheogorath, the Mad God and Jyggalag, the Daedric Prince of Order from Elder Scrolls IV: Oblivion.
This could answer the question, what is the Fae and the Glade doing during the events with the Aspects and the Darkin? Surely the Fae has a stake in the fate of Runeterra, and thanks to this Fae, Lulu is the only hope for the Glade and the Fae. This would thrust Lulu into the spotlight, instead of just being a quirky background character in the lore.