so maybe I had a wrong idea about what a wild card meant.
I thought it was something huge a studio could have in store that they could announce/do as something that almost everyone didnt expect, but at the same time being something huge they wanted since many years ago.
For example: fans wanted a long series after X2, and even after X3, fans wanted X4 too, with Cyclops, Kurt and company. but after all these years, the Wolverine movie and First Class, most fans lost hope on X4, so if Fox announced it now, that would be their "wild card", their 'final' best card to Win the full game.
That's how I understood the wild card, at least, lol.
The last big card to make you win the game. Feels logic at lest
Next Big X-Men Crossover
* 2017- X-Men: Age of Apocalypse
Edit: Forget about 2017:
Official announcement -> X-MEN: APOCALYPSE - MAY 27, 2016!!!!