If the Grundy player is letting you do anything of the following, he isn't real:
Abuse wing dings, Grundy doesn't struggle with these at all really (Tyrant even backdashes MB wing ding if he feels like it)
Not hit for at least 50% everytime he touches you
Mb walking corpse into 50/50 game that can also reverse wakeups
Anti air every jump you try to do, including staff
Punish every interactable you try to use
Punish you for 50% if you ever forget you can't do mb staff spin on him
Make you respect 112 cancels until you prove you know how to get out
The NW/Grundy matchup isn't even close to one of Grundy's worst. That's just a common misconception from early play. If you want to watch a bit of Tyrant and myself playing,
then here is this.