Battle Dragons, now known as Defender Dragons, are a different type of dragons available in Dragons: Rise of Berk. They can be obtained through collections that always involve collecting gears after winning a Fleet Mode battle. They will then be released from one of Drago's traps. These dragons fight better than others of the same species but have less good fish and wood collection stats.
These dragons have been suited in metallic armour by Drago Bludvist and Eret, Son of Eret to build Drago's dragon army and enhance their performance in battle. At the end of the second film, these dragons are rescued and inhabit Berk.