I use the explosion height setting of 2. Simply if you set it to 3, the explosion height will be numerically equal to its radius. However, the cells of the battle map are not cubic, their height is greater than the width, and if the height and radius of the explosion are equal, it will also be elongated vertically - not a sphere, but an ellipsoid. Whereas setting to 2 gives the maximum approximation of the explosion to the sphere. I don’t remember where I read the justification for this, but I agree with its correctness.