Since SpecialK and I have been in contact with each other again, we have been playing Magic: The Gathering (MTG) - a card game that simulates us being fantastical spell casters in battle against each other. While it may appear to be a kids card game on the surface, it does lend itself to managing resources (in the way of obtaining mana to "pay" for spells), as well as understanding probability when attempting to build decks to compete against each other.
While it is simple enough for a casual player to walk into a MTG store and buy a deck to start playing, the next level of understanding of the game is when you start creating your own decks. With some simple rules - like no more than 4 copies of any card besides basic lands, you have to construct a deck that attempts to beat your opponent down from 20 life to 0, or gives him 10 poison counters, or fulfils some other win conditions - without your opponent doing the same to you.
SpecialK and I took that concept one step further by having a limited sealed game with just him and I. We opened up 6 Rise of the Eldrazi boosters, added some lands, and made a deck of 40 cards. We would later add some Zendikar booster to the mix as well. We played this over the course of around 3 weeks. Every time we met, we would add one booster to our respective pools, and attempt to come up with a deck to beat each other. SpecialK kept reusing his first deck, and just substituting a few cards from it here and there. I would swap my entire deck in and out. One week I would play one combination, and another week I would be playing a totally different combination of cards. In this format, the 4 card maximum rule does not apply. The only rule that does apply is that you cannot add cards from outside of the packets you have opened.
In a way, this simulated the type of format used in some MTG leagues that are held in the card shops around Melbourne. While I am not doing well at those types of formats, I do enjoy myself when I play this game.
At the end of the simulation with SpecialK, it ended up roughly even, with me possibly edging ahead with an extra win or two. It also gave SpecialK an insight into MTG, a game which he thought was originally dead and no longer being played. I do not know of a time where it has been as popular as it is now.