this also sounds like there is a new type, like asking how many possible are there, it sounds that now there are more possibilities --- Pokemon Black FC: 0605 0891 4299 Pokemon Black 2 FC: 4814 4999 6059
Well gen 1, 2 and 4 had some, and 3 and 5 didn't. I think it's due.
I always thought of using a bottle of special poison as a hold item which makes it evolve on trade by killing it... thus making a ghost type.
A bit hardcore don't you think :P
Anyways,. Yeah Gen 4 had them, Then Gen 5 wanted to have only Gen 5 pokemon (in the first games B/W1), so thats a no. Now Gen 6 has old pokemon in their game again. --- Official Great Toad Sage of this board.