Somewhere in the dunes of the Okoto desert a tall figure was roaming the sands, at first sight one could confuse the figure with Pohatu the Master of Stone, but on a closer look it would become obvious it is not him. This was a female warrior, though her mask was quite similar to Pohatu's, those who saw her didn't recall a seventh Toa of such to arrive along with the rest. Though she did help out on occasions when the protectors needed some help her main mission seemed to be still unknown, though she did often ask about where can she find Pohatu, but for what reasons she never shared with the others.
Or it could be Master of Speed if we wanna go with the current way of naming Toa, but either works for me. Well Year of Rebirth spawns another of my older creations in an updated and far superior form. Small thing about Sonnax just for the fun of it I made her be a fangirl of Pohatu, though that is not part of her actual story, it's just a simple, goofy little thing. Plus since the current Pohatu is Mr. Deep edgy voice now, I'm sure her being a fangirl will only make her want him even more Though it'll be an awkward sight as she is 1.5x the size of Pohatu.