Yo Marty, Could you check out this game-breaking mechanic? https://www.youtube.com/watch?v=5rzKTt0LEUk I know that it isn't implemented in Showdown but check it out.
PS: In the comments there's a list with all the items that are affected by this mechanic
PS: In the comments there's a list with all the items that are affected by this mechanic
In Gen 4 it just said "POKEMON’s Forewarn alerted it to MOVE!"
Incidentally that's also why it's now officially illegal to nickname two Pokemon identically, or nickname one with the species name of another, to avoid confusion on messages like this.