It's interesting, because this ability was introduced in Legends, which had exactly 310 cards and it introduced 3 new rules: Legends, Enchant Worlds, and Bands with Other
Sorry, Upper Deck
3 Lost World Call Of Legends (81/95) Lost World, from the Call of Legends set in 2011, was the first card with an instant win condition: if your opponent has six Pokemon in the Lost Zone, you win the game
Whats more, Vashta Nerada can get a +1/+1 counter every turn, including when the opponents creatures die
I had said in my last post that I think this is a fake which originated in the US but based on taking another look at this I think its a bit too basic
At the beginning of your next end step, exile it