It's... okay. If you lack removal it's serviceable in Gx ramp/stompy, but by the time you get to six mana in this format, three damage probably isn't doing nearly enough. It's similar to Vial of Poison; your opponents will see it coming often enough, and it will likely require you to 2-for-1 yourself in order to take someone down.
I'd rather side it in (vs evasion) than side it out (vs monsters or good heroes.)
Yeah, in sealed it's perfectly fine removal for decks that are removal light. In draft, that's not so much an issue unless you drafted badly so...I guess it's for decks that didn't quite work as planned and they can't afford to replace it with a 20th land?
I'd only play it if I were running a Monstrous-based ramp deck. In that case, I'd likely be short on cheap castables, confident in my ability to get to 5+ mana, and not wanting to get into a situation where my opponent is dropping chump blockers to stave me off.
It's still not great, but it's playable in that kind of deck at least. And it is a removal spell that you can grab pretty late in a pack, so if you need a removal spell, you can at least be pretty sure you'll be able to get one.