Nintendo Bans Two Moves in Pokemon Sun and Moon Temporarily Pending Fixes
Your game could crash with these particular moves.
If you've been enjoying Pokemon Sun and Moon since its launch, you've no doubt ran into plenty of peculiarities in the game here and there, namely some glitches that occur when special Z-Moves are utilized. Some of the moves will cause the games to crash entirely, making them (quite obviously) frustrating to deal with.
So if you use either Memento or Parting Shot when it comes to launching all-out offensives against your opponents, you'll find that they've been banned from all online elements of Battle Spot, like Free Battles, Rating Battles, and Online Competitions. If you happen to rely on these moves at all, it might be a better idea for you to play alone. But if you're like most players these aren't exactly the most important parts of your repertoire.
Nintendo is working to resolve the glitch and keep it under control with a special patch going forward, so this is just a temporary resolution for the moment until things can be taken care of. Given the fact that Pokemon Sun and Moon are the fastest-selling games in Nintendo History as far as the Americas are concerned, there's a lot of players that could potentially be affected. Hopefully it's all cleared up soon.