In Showdown, I was up against my opponent. I was going to use Seed flare against the opponent's Sharpedo. Sharpedo used Ice fang and froze Sky-Shaymin. Sky-Shaymin reverted to Land Shaymin. How and why did this happen? What happened to Shaymin? This was on National Dex AG. Battle Replay: https://replay.pokemonshowdown.com/gen8nationaldexag-1211007148
Shaymin-Sky will revert to land form if frozen
"Shaymin's Sky Forme will revert into and remain in its Land Forme during the night or when frozen. Other circumstances may also cause it to revert."
Source: https://bulbapedia.bulbagarden.net/wiki/Shaymin_(Pokémon)