I haven't played the card game in a "league event" in probably ten years. Maybe more. On a whim, I went to the Prerelease Event for XY Evolutions and had a great time. Now, I'd like to start playing again. The thing is, almost all the cards I own are OLD - going back to first series, through maybe Team Rocket, maybe the expansion just after that. I have no idea if any of those are playable - although some would seem to be since, for example, XY Evolutions has Double Colorless Energies (to grab a card at random).
The answer may be harder than I am hoping for but is there a simple way to tell what cards I can play with and which I can't? Clearly, I can play with XY Evolutions cards. What others? Would greatly appreciate some help!