This particular card doesn't seem solid at all until we see the rest of the stat. Tyrantus would be a good example of a good beast but outside that, this is way too specialized to be usable. Perhaps, the loa would make this more powerful.
Turn 10 mana Spiritsinger Umbra into this card pulling the obvious Hadronox sounds good to me. One really can't underestimate how vulnerable you are that turn you're forced to play a tempo Hadronox because naturalize isn't getting drawn
In other druid decks, this is yet another card you can play arcane tyrants with for that big tempo swing
Well if there will be more good late game beasts like Tyrantus and Oondasta, I can see this one definitely working out in beast based ramp druid, instead of dragon one that we have right now. Heck even summoning Giant Anaconda, trading it into a minion and summoning another big one is a big tempo play on 6 mana. In general this is a very good card, question is how much support will it get.