Alexander, just like Chili, wasn't intended to be in the Tree of Life story at first. But just like with Chili, it just happened at some point. His appearance added so much to the story, we just had to properly write him into the Tree of Life world. With that came some design changes, a lot of personality changes, and (I'm pretty sure a lot of you won't be happy because of this…) these changes kinda made the “Gift from the Water God” comic non canon. I mean, kinda. Maybe only half of that story is canon? It's complicated... But you'll see from the Tree of Life comic.
So Alexander is the god of water. (Not a huge spoiler, don't worry guys.) And as a god, he has divine powers, and can control/create almost anything related to water. During those hundreds and hundreds of years he has been alive, he saw and experienced a lot wandering the world, in some cases maybe even more that the Tree of Life herself. But even with the strength and limitless power that came with godhood, he never forgot what it means to be a weak mortal. (That's right, at one point, just like the other gods, he was just a simple mortal man.) But will Alex be strong enough to fight against the rule of chaos?