After playing our first game, we had an issue with my son standing on the Major Score mound and two walls on either side. What prevents a player from using two place walls cards and completely surrounding themselves with walls? Yes, it would take two turns to do, but seems doable. At 5 points a turn, this could end the game very quickly. I fortunately was playing Ogres and just stomped and knocked him down and went in the open edge and took the ball.

I am considering a house rule of - No More Than 2 Walls May Be Placed On A Single Space.
This would ensure that even on the board edge, there would always be at least on open side of a space.

Thoughts?