There’s a flash game(I think?) that I liked to play when I was younger called How to Raise a Dragon. It has four stages where you play as a hatchling, adolescent, adult, and a knight(this one heavily determines your ending). There are quite a few endings, but you ultimately decide how it ends.

Choice of The Dragon is a fun text based choose-your-adventure game. You play as a young dragon who encounters a kingdom and progress through a storyline filled with fantasy shenanigans. Your choices affect the personality and abilities of your dragon, which is pretty neat. You can be a beast that destroys villages for fun, become a thustworthy protector, a cunning smooth talker, and everything in between.

Does Dragalia Lost count? It’s a mobile gatcha rpg with human characters, but dragons are an extremely important part of the lore, and are their own characters. One of the main mechanics is transforming into your dragons so you can totally wreck enemies and bosses. It’s fun, and the catchy music slaps.

About Day of Dragons, I found something very similar, but it actually has a good chance of making it out of development. It’s called Draconia. It’s not out yet, but the developers are being very transparent about its progress, and give out frequent updates and pictures on what they’re working on. It’s also a survival game where you play as dragons, but there’s a variety you can pick from. There’s no set release date, but they’re planning to release it on Steam, and it already has its own Steam page :)