Dont think dragons will be a player race. You are talking about the massive 4 legged crazy flying fire breathing things arent you. Your idea sounds good i guess but i doubt the devs will implement it. I wouldnt want to play as a dragon but riding one hell yes.
For example you discover a dragon egg. You keep it in your house properly incubating it. Until finally it hatches into a small baby dragon. Now this takes time to grow , you need to feed it every once and awhile and make sure it gets plenty of exercise e.g attacking stuff. Eventually it grows into teenage dragon , its alot stronger and bigger and can be wridden like a horse but it cant fly yet. THen eventually it grows into a full dragon , here you get to choose its skills , e.g heavily armoured or improved fire breathing or w/e. With the full dragon it is a flying mount and has mounted combatlike fire breathing or w/e skills you chose.
Something like this i would like. Ofcourse it couldnt be to overpowered
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