Two of the three cards from last week's post I've gotten from such playtesters, and the third came from Keith "The Misprint Guy" Adams about three years ago (after he had visited original playtesters himself)
[P] Energy Absorption - Attach up to 2 Energy cards from your discard pile to Mewtwo ex
Well, obviously the regular sized TCG cards have released by now
Within the sets cards, there was a new theme, Sword, which featured a host of powerful characters
More thought about the product
I think this deck is very mana-hungry, but it can also slow the pace of the game way down, and with all of the filtering of your draws you'll get later, you'll have the mana you need just by virtue of hitting all of your drops and finding all of your rocks