Cryonis

is a Rune in.

Location and Uses
The Cryonis Rune is obtained in the Keh Namut Shrine at the Great Plateau. The Cryonis Rune allows Link to spontaneously create pillars of ice from the surface of any body of water, including waterfalls. Link can create up to three pillars of ice at once; raising a fourth one breaks the first. In addition to creating pillars of ice, Cryonis can also be used to break these pillars as well. After using the Cryonis Rune to create a block, a timer gauge will appear which must fully restore before Link can use Cryonis again.

The ice pillars created have various uses, such as creating stepping stones, getting leverage and making obstacles. It is also used to manipulate certain surroundings, such as opening a gate by raising a pillar beneath it. Cryonis blocks will break if the water they rest upon evaporates, or if a hidden Korok travels underneath them. Cryonis blocks can be placed on Bottomless Bogs, but not on Hot Spring water. Cryonis blocks can be destroyed with the Remote Bomb Rune, though they are impervious to Bomb Arrows. When struck with Ancient Arrows, Cryonis blocks will disintegrate, leaving the Ancient Arrow behind. Blocks made from Cryonis are impervious to all other Runes, Weapons and Arrows.

Divine Beast Vah Ruta and Waterblight Ganon are capable of summoning Cryonis blocks as well as spiked balls of ice. However, like all other Cryonis formations, these can be destroyed with the Cryonis Rune.

Nomenclature
The word cryonis comes from the Greek cryo or cryos (κρύο) which means "icy cold."