I have since talked to Matthew on Twitter, and he said the cards are a thank you for the contest. If you haven't followed him yet, now is as good as a time as ever. He is great guy and posts awesome cards. He is also currently holding a contest for a Paco Rodriguez autographed card, with more contests planned in the future.
The first thing inside was this Yasiel PUIGGGGG card from 2013 Bowman Chrome. I am pretty sure there are two variations of this card, but my memory is failing me. I sent over a similar card to Matthew a few weeks back in a trade, however I sent the pricier refractor version. This is one of my favorite cards from 2013, and I suppose a Top 10 cards from 2013 should be a priority for me. Considering we are already a month and a half into 2014, I don't see it happening.
In fact, I got some matching Shawn Green cards to go along with my new Beltre's. These come from 2003 UD Victory, and feel more like playing cards than baseball cards. I think these are also my first "Green Goatee" cards. With these two additions, my Green PC now sits at 43 cards, yet these are the only cards in which he is rocking facial hair.
Thanks for the cards Matthew. I appreciate the love.