What's up with this Metal Slug copy?

[Protoman]

http://img.tradera.com/images/327/176571327_561a154e-00ef-4a17-a03e-4462e78bd549.jpg

http://img.tradera.com/images/327/176571327_ada24676-6b3b-49e3-abae-27e8cc02d3da.jpg

The cover to the american version when I google it looks like this
http://www.neo-geo.com/snk/carts/us/metalslug.jpg

So what am I looking at? A reproduction? A fake? A rare version/cover?

[Ghegs]

The cover is a fan-made one, meant to be used with shockboxes for MVS carts. See it here.

I'm guessing that's an MVS Metal Slug converted into AES. The MVS cart goes for around $50, while the the AES release is $500 or more. It could be an attempt to cheat some AES collector out of their money (though a poor attempt it would be) or the creation of someone who just wanted to play Metal Slug on their AES system without paying for the original cart. In any case, it's not an original, legitimate cart.

[GohanX]

Sorry for the late response, but yeah, it's either a MVS to home cart conversion or an outright bootleg. The artwork is from the Metal Slug Neo Geo pocket game, possibly used by the creator to show that it's not an original cart. I made one myself and did something similar so that if the cart ever left my possession nobody could sell it claiming it was anything other than a conversion cart.