I've written for as long as I knew how! I currently have two fantasy projects I'd like to get published eventually, both in early 18th-century settings (because you don't get much of that in the fantasy genre for some reason). One is a totally original world, and the other is a sort of urban/historical fantasy, I guess. Second drafts are almost done for both of them. I've written about 180k words per year the past couple of years...sheesh. The original story is one that had its original incarnation almost 20 years ago, with some characters being even older than that! It first was a sci-fi, then a sci-fi/fantasy, then high fantasy, then sci-fi again, then high fantasy, then 18th-century fantasy, which suits it very well.
The historical fantasy story hasn't been around for as long but it seems like every time I touch it, I find something else I need to research in more detail

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When I need a break from those, I write Transformers and Legend of Dragoon fanfiction. Both of which have been ongoing for 12+ years!