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1. Head to the bar and pick up a big jug of something to drink while you are doing the rest of the steps.  (Yes its period - documentation is at the end.)
2. Sit down somewhere comfy with a friend or, lacking any handy friends, grab the first person that walks by and sit them down with a drink.
3. While drinking sort out what set of rules you are going to play by and what size board you will be using.  The rest of this article is the version I like most.
4. Grab your knife and carve a quick grid into the table in front of you.  Make it 13 squares by 13 Squares.  Put an "X" in the center and in each corner.
5. Grab a big piece of antler and put it in the center square.  This is called the King.
6. Place twelve smaller pieces of antler in four groups of three going out from the center square to each principal direction (top, bottom, left, right).  If the drink is going to your head there’s a picture below. These are the defenders.
7. Grab 24 rocks.  Place 5 of them on each edge of the board centered along the edge.  Place the remaining 4 rocks just inside of the groups of five on the same lines as the three defenders.  The rocks are the attackers.
8. Decide who is attacking and who is defending.  Hint - according to the sagas the defender usually wins but the attacker moves first (its an attack after all).
9. Play and drink.  (I said its period didn’t I?)

1. There are no diagonals in this game. 
2. Every piece has exactly the same move - as far as you want in any of the principal directions.  Yes the king too.
3. The attacker is trying to kill the king.
4. The defender is trying to get the king safely to a corner.
5. All of the squares with "x" in them belong to the king.  No-one else can stop on those squares.