South-east rule

The south-east rule (formerly known as the south-west rule, because of the fact the X coordinate value previously got greater further west) is an unintentional mechanic in Minecraft wherein various effects occur based on the cardinal directions, specifically in a south-east variant. It could be better described as the Z-X rule, as the rule as always acted towards positive Z and positive X.

Effects
Here are some of the effects that happen in Minecraft that have to do with the south, east, or south-east cardinal directions.
 * Rails will curve south or east when they are initially placed at a "T" intersection or a "+" intersection. They will also curve away from the south or east when powered.
 * Mobs being spawned by spawn eggs, spawned by monster spawners, built by the player, and newborn baby animals will always appear to be facing the southern direction.
 * TNT cannons tend to fire farther when facing east or south. Designs that don't account for spread also exhibit horizontal drift eastward/southward as well.
 * Many bugs cause problems relating to south and east, such as villagers trying to cram into the house that is mostly in the southern-eastern area of the village.
 * Levers facing north or south will always have the off state pointed south and levers oriented east or west have the off state directed towards east.

Trivia

 * The debug screen displays direction using the value "f" under coordinates such that 0 is South, 1 is West, 2 is North and 3 is East.
 * There are some exceptions to the south-east rule. For example, if there is an intersection in a Minecart track while going downhill, the Minecart will choose the downhill track, even if the south-east rule applies. (see Rail)