It has 200 hp, but only 50 in defenses. It also has 100 in both attacking stats, and so it fits awkwardly in both roles, but it also basically gets a dragon type water spout. So is it better defensively or offensively?
It gets Dragon Dance to make its Attack and Speed better, boosting its offensive capabilities. It can also set up dual screens for support and better defensive capabilities. It can function as a mixed attacker or lean to either physical or special, making it fairly versatile. I think it's a little soon to say for sure, but I believe Regidrago is better as an attacker.
Hope I helped!