In Limited, this is really good if you amass the power which is not too hard to do in Khans Limited. Is it good enough for Constructed, though? 2R seems well worth paying for that kind of power, but 8 power that can be easily chump blocked isn't so fabulous. It's probably going to be Limited playable only.
Crater Elemental looks like a card that could be a lot of fun, but this doesn’t outclass anything being played in Constructed Aggro decks at 3 mana like Goblin Rabblemaster or Mantis Rider. But there are also casual connotations as creatures with big power potential always seem to find a home. Elemental tribal is sort of a thing, you know.