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-A prototype multiplayer stealth strategy game
+A prototype multiplayer stealth strategy game.
+
+## Usage
 
 ```sh
-# Run the server locally with 2 players
-cargo run --bin server 127.0.0.1:50000 2
+# Run the server locally on port 50000
+# 4 players, 5 guards, 48x48 map, 1 minute turn time
+cargo run --bin server 127.0.0.1:50000 4 5 48 1
 
-# Connect the client
+# Connect a client
 cargo run --bin client 127.0.0.1:50000
 ```
+
+## Gameplay
+
+The game is played between 1 *defender* and a number of stealthy *attackers*.
+The defender controls a set of guards who can view parts of the map.
+An attacker controls a single agent who must sneak past the guards to their
+objective.
+
+### Defender
+
+On a defender's turn they control the guards with the following actions:
+- `TAB` to cycle through selected guard
+- `LEFT` to move one tile left
+- `RIGHT` to move one tile right
+- `UP` to move one tile up
+- `DOWN` to move one tile down
+- `[` to rotate field-of-view anti-clockwise
+- `]` to rotate field-of-view clockwise
+
+A defender has 8 actions per turn (not including cycling through their guards).
+
+To eliminate an attacker, a guard must manoeuvre such that an attacker would take
+3 or more moves to escape their line-of-sight. Note an attacker is only visible to
+the defender if they're within a guard's line-of-sight.
+
+![Defender play screen](./images/defender_play.png)
+
+When it is not their turn they will be presented with a waiting screen:
+
+![Defender wait screen](./images/defender_wait.png)
+
+### Attacker
+
+On an attacker's turn they control a single agent with the following actions:
+- `LEFT` to move one tile left
+- `RIGHT` to move one tile right
+- `UP` to move one tile up
+- `DOWN` to move one tile down
+
+An attacker has 5 actions per turn.
+
+To eliminate a guard, an agent must manoeuvre to occupy the same tile as the guard.
+
+![Attacker play screen](./images/attacker_play.png)
+
+When it is not their turn, or if they have been eliminated,
+they will be presented with a waiting screen:
+
+![Attacker wait screen](./images/attacker_wait.png)
+
+#### Win conditions
+
+For the defender:
+- eliminate all the attackers
+
+For the attacker(s):
+- all attackers reach their objective locations, or,
+- eliminate all the guards
+
+#### Legend
+
+- `.` floor tile
+- `#` wall tile
+- `A` an agent
+- `G` a guard
+- `X` an objective location
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