According to the epochs, the Architect have created the Ancients as an improvement over the native flora and fauna on the planet. All of the ancients, Neow included, started out as tiny seeds and grew into different trees shaped by its surroundings. Eventually, as a tree reached full maturity, an ancient is birthed from the tree.
Neow was jealous of the Architect. So she devised the Blight to incapacitate the Architect to grow her own tree. Captured by her peers and then out cast, Neow's tree fused with the Blight and robbed the land of its nourishment, until it too lost its branches and foliage and became the Spire we know today.