In DragonVale for the iPhone and iPad, the Bronze Dragon is Treasure Dragon similar to the Gold Dragon, Platinum Dragon, and Silver Dragon.
The Bronze Dragon has a base breeding time of 46 hours, sells for 3,500,000 coins, and earns 450,000 XP for successful breeding once you reach level 17.
To breed the Bronze Dragon, you must mix dragons with the Earth and Metal attributes. Earth + Metal or Earth + Chrome are good examples. If you get a 46 hour incubation time then you’ve got it.
Check out my DragonVale Breeding Guide for more dragon breeding combinations.
