So, it goes like this. You need a board of any size, a chess one or slightly larger should be enough, 2 types of small colored flat circles, two distinct pieces, and something that can be pointed in any direction. This is like one of those artillery games as a tabletop.
Let's hope I explain this well.
This is the recommended board for first-time play.
The blue circles are rock. It can fall. Will be explained more later.
The black space is empty space.
Gravity pulls down.
The @ symbols are the two players. They can shoot.
Okay, you didn't get it. Explaining more!
SHOOTING:Either of the players can fire a projectile on their turn in any direction. The projectile can be launched at speeds 0 to 4. It travels the number of squares specified when launched, 0 to 4, before changing the direction of travel or falling straight down. When it hits a rock/player, both it and the rock/player are destroyed. Once a projectile has changed trajectory or was destroyed, you may take a turn. The projectiles slow down after every trajectory change. Bullets advance everytime a player takes a turn.
Say, I launch a projectile diagonally upwards with a power of 3. It flies diagonally upwards 3 tiles, then changes direction to horizontal for 2 tiles, then it changes direction to diagonally downwards for 1 turn, then it slowly goes down at a rate of 1 tile/turn.
MOVEMENT:Players can move in all unoccupied directions, but in practice, this means they can climb stairs and walk on straight surfaces. If a player falls down more than their own height, they die.
ROCKS AND DYNAMITE:Rocks can fall down or collapse when falling, killing or detonating players/dynamite below,
instantly, akin to cave-ins from Dwarf Fortress. It falls like this: If the rock is falling, if it has no surface below it, it falls straight down. If it has a surface below it, but not diagonally down, it falls down diagonally. The diagonal fall direction that takes precedence is the one closest to the center of the playfield. Otherwise, it stays still.
Dynamite (represented by a red disc) is a special type of rock. When it falls down more than 1 tile or is shot, it explodes, destroying everything in a 3x3 square and exploding dynamite in that square, potentially causing a chain reaction. Dynamite can be picked up and fired like a normal shot, exploding upon landing, but it can collide with your or enemy shots and explode.
WINNING:If one player is killed while the other is still alive, the other player wins. If both die at the same time (dynamite accidents...), it's a draw.
Sorry for any inconsistencies.
SUGGESTIONS WELCOME