Valuable card or not? Please help.

I have picked up a Black Star Promo XY42 Groudon EX and have noticed a couple of things:

- The illustrator is named 5 ban Graphics (I know this is a common misprint).
- All of the corners barring the top right have a rounded cut, the latter having a square cut.

The card seems 100% genuine and I'm an avid/veteran Pokemon card collector, having collected from day one, so I know that people have bought uncut sheets from companies and square cut them to try and make people believe they're valuable, but I've never seen anything like this before.

Any fellow Pokemon TCG nerdiness is highly appreciated =]

Its a tin promo I think so its not worth that much also for future reference there's a stickied thread for these questions at the top of the page :)

I'm fully aware of where it's from, as I'm currently collecting promo cards. It's the fact that it's square cut on only the top right corner, which is something I've never seen before. I've seen miscut cards, where you can see the dots that the laser uses to cut them at the factory, misaligned cards, where you can see the image hasn't been centred properly and square cut cards on all sides, where people have bought a sheet of Pokemon cards and cut them themselves to give the impression of a miscut.

Here is the card in question, now that I can actually upload pictures:

Miscuts like that aren't really going to be all worth all that much more than their non-miscut counterparts, as though they have people who seek them out, there's a lot of people who also deliberately do not seek them out. Maybe $1 to $2 more at most compared to value of a normal one, if you're lucky, that is.

I have absolutely no intentions of selling it, it would have been a great find if the strange way it's miscut would've added some value.