I dunno how you want rarity quantified, but according to the Monster Invasion website, it's card #171 and it's ultra rare. That makes it more common than "Super Rare 3-D" cards, but less common than "rare" cards. I've looked around for actual probabilities to no avail — but I can tell you that someone out there thinks they're rare enough to offer 'em for £12.99 a piece. If the ordinary laws of supply and demand are at work in a market economy, that seems plenty rare to me.