Spring

A spring is a single unit of liquid that generates within the world, flowing out into spaces level with or lower than the source. There exist three main categories of fluid springs.

Normal springs
This most familiar type of spring can generate as either water or lava, and generate in the sides of stone surfaces. These are commonly encountered on the sides of cliffs, as well as inside caves. Lava springs are a common source of forest fires.

Normal springs do not generate above a certain altitude. If the Caves & Cliffs experimental gameplay toggle is enabled $$, springs are unable to generate below Y=0, though runoff from them is able to flow below that height.

Ceiling springs
These types of springs are exclusive to the Nether, and generate only as lava. As their name implies, they generate on ceilings, and the liquid flows directly downwards from them. These are quite common sightings in the Nether, and the resultant lava spreading can sometimes make traversing terrain difficult.

Hidden lava
Unlike the other types of springs, these are hidden from generation. These are particularly dangerous and care must be taken (like taking a Potion of Fire Resistance) when mining in the Nether, as they can be dangerous when uncovered.

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