Assuming you mean Pokémon Ultra Sun patch/update 1.2 (game update for Nintendo 3DS), key features and changes typically included in a minor version update like 1.2 are:
Because of this "glitch in the Matrix," the Alolan authorities—known in our world as Play! Pokémon—were forced to ban these moves entirely to keep tournaments running. For a while, the strategy of slowing down opponents with sticky silk or swapping stats with a Power Trick was lost to the wind. But on February 7, 2018, everything changed.
: Due to the fix, these four moves were officially unbanned from Play! Pokémon video game tournaments. Ion Deluge : Resolved an issue where the move Ion Deluge would fail to function correctly. Online Requirement pokemon ultra sun update 1.2
Yes — in a good way. The official VGC (Video Game Championships) rules for Ultra Sun & Ultra Moon require version 1.2 if you’re playing on a modded or updated console. Without it, your battle videos may desync or fail to upload to the Global Link (though note that the 3DS Global Link service has since ended).
Battle Spot: Preventing "version mismatch" errors where one player’s game might process a bugged move differently than their opponent’s. Assuming you mean Pokémon Ultra Sun patch/update 1
Is "Update 1.2" Real?
If you’re still making your way through Alola — or revisiting it on your 3DS — you might have noticed a small but significant update for Pokémon Ultra Sun (and Ultra Moon). Version 1.2 quietly dropped a while back, and while it doesn’t add new story content, it fixes a few critical things. But on February 7, 2018 , everything changed
If you still have your cartridge on Version 1.0, you cannot transfer your Necrozma or your event-owned Zeraora to Pokémon Scarlet. The update quietly installed the cryptographic key needed for that final transfer wave in March 2023. Without 1.2, your Pokémon are stuck in Alola forever.