Water! Earth has a bounty of it. Many of us don't even think about how weird water is as a substance because it is so commonplace on the planet. One of the strangest properties of water is how it expands when it freezes, rather than shrink like a vast majority of every other substance. There are consequences to this weird increase in volume when water turns to ice. On Earth, that conversion can turn solid rock into debris as water expands and contracts when it freezes and thaws. Water is a powerful agent of change during its change from liquid to solid.
Thing is, water on Earth is a real anomaly. No where else is so much liquid water found on the surface. If you look at the rest of the solar system, water tends to be found in its solid state at the surface of asteroids, comets or outer planet's moons. Some of those moons, like Europa, Callisto and Ganymede around Jupiter, Enceladus around Saturn and Triton around Uranus and even dwarf planets like Pluto are covered in ice layers that might be hundreds of miles thick.
