I came up with an option for playing 2x2 with a single board. (I didn't see this idea mentioned specifically, but I could have missed it).
The board has 12 zones. However, there are a total of 14 Wall sections on the outside of the board. I figure that Zone-Exclusive cards that don't affect a specific space can be summoned (installed?) in a wall section. Thus, things like Mana Flower and Mana Crystal can get installed in the mages' arena outer-wall sections. Zone exclusives that require a specific space (such as Spawn points, etc) have to be in actual zones.
For attacks to destroy a zone-specific conjuration in a wall, the attacker can only do full attacks--which would be equivalent to being able to make the extra zone-move as if the conjuration was in the next zone outside the board. Thus, an attacking creature cannot move into the wall zone and do a quick attack against the wall; it has to start its turn in the space connecting the wall. Also, the wall cannot be targetted by attacks that target everything in the zone, such as Ring of Fire, because for all intents and purposes, the wall is its own zone.
What does everyone think? This adds spaces for non-moveables with a single board.
