Hail doesn’t boost the power of Ice-type moves, it doesn’t activate any Speed-boosting abilities, nor does it grant any additional healing outside of the limited distribution of Ice Body. So for many OU players the question is really, “Why use hail?”. What hail does is offer some unique qualities to many teams that use it.
Then, is Hail the only weather-inducing move not introduced in Generation II?
One source stated that This makes Hail the only weather-inducing move that was not introduced in Generation II. This article is part of Project Moves and Abilities, a Bulbapedia project that aims to write comprehensive articles on two related aspects of the Pokémon games.
You might be thinking “Is hailstorm a TM move?”
Hail (Japanese: あられ Hail) is a non-damaging Ice-type move introduced in Generation III. It was TM07 in Generations III through VII and is TM35 in Generation VIII. When Hail is used, a hailstorm will begin on the field.
Hail is apart of the weather lineup of moves. While Hailstorm is generally considered to be the weakest weather condition, Ice Types can make great use of it. Each turn, all Pokemon that aren’t Ice will lose a bit of their health at the end of it.
How does hail work in Pokémon Go?
When Hail is used, a hailstorm will begin on the field. This effect will last for 5 turns. This clears any other type of weather. While Hail is in effect, all Pokémon not of the Ice type will be damaged for 1⁄16 of their maximum HP at the end of each turn. Synthesis, Morning Sun, and Moonlight will recover only ¼ of the user’s maximum HP.
Effects Hail creates a hailstorm that lasts for 5 turns and induces these additional effects: All Pokémon lose 1⁄16 of their max HP at the end of each turn, except Ice types and those with the abilities Ice Body, Magic Guard, Overcoat or Snow Cloak. The move Blizzard ignores accuracy.