This is a game that I saw in a book long ago. Unfortunately I cannot find the book now, and even if I can as I recall it does not provide a strategy. I will be very grateful if you can provide me a link to the authoritative rules of the game (and verify that I didn't remember any part wrong. Edit: @DqwertyC provided a link to the rules of the game "Aggression" which I believe is the authorative version ), but of course I am more interested in the best strategy, which I don't know, either. You may consider the rules below as an adapted version of the game but please clarify in your answer which set of rules you are using.
The game only requires a pencil and a piece of paper, and optionally a calculator (as stated in the book) if you are not good at maths or are simply lazy.
The game is played between two people (Alice and Bob). Before the game they agree on an odd number $N$, which should be significantly smaller than 100 but not too small. See the rules to get a rough feeling on how large $N$ needs to be to make sense.
The game has three stages.
Stage $\rm I$. Generating the Map It begins with Alice drawing a closed curve on the paper, dividing the paper into two parts; the inner part is the current map (with a single region). Then Bob draws another curve to add another region to the map. The new region must be adjacent to an existing region and cannot fully encompass an existing region. Then it is Alice's turn, and it goes on. After the $i$th move, there should be exactly $i$ regions in the map, and each region should be adjacent to at least one other region, and no region can fully encompass another region. This stage ends after exactly $N$ moves, and there will be $N$ regions in the final map.
The rule that no region can be fully encompassed by another region is a rule that only exists in my adapted version.
Stage $\rm II$. Occupying the regions This round starts with Alice. Alice can choose any region from the map, mark it with her favorite pattern to occupy it and attach an integer between 0 and 100(inclusive) to it. Then Bob chooses a region, marks it and attaches a number to it. This goes on until all regions are occupied. There is, however, one restriction on the attached numbers. The sum of the numbers attached by any individual player cannot exceed 100.
Stage $\rm III$. Conquering This stage starts with Bob. Bob and Alice take turns to make a move. At each move, the player can choose to skip (do nothing), or he can choose one of his opponent's regions that is adjacent to one of his regions, and conquer it following the rules. The rules are:
- the attacking region's number must be strictly greater than the number of the attacked region
- the attacked region must not have changed hands in an earlier move (i.e., each region can be conquered at most once).
Attacking does not change the number in the attacker's region, nor the attacked region. In fact the numbers attached to all regions are fixed once Stage $\rm II.$ is complete.
This is different from the authorative rule of a "Aggression". In my adapted version, the "troops" in the conquered region can be used in a later stage.
This stage ends when both players choose to skip.
Goal of The Game After stage $\rm III$, the player with the most regions wins. The attached numbers are irrelevant.
If there's anything unclear about the rules, feel free to ask. I will be happy to follow up.
Now try to find out the optimal or the suboptimal strategy, smart brains!
Side note: It is not clear in the authorative version who is the first to make a move at each stage. I believe that can make a really big difference.