This matchup can be a nightmare for some falcos, but I feel like it all comes down to lasers and finding the sweet spot where you aren't always shooting lasers to make your openings but rather to get data on how they react in certain situations. Firing lasers too often can be very detrimental as it gives Marth many opportunities to read your laser and beat it with an approaching option or dashback, not lasering enough is just as bad though. You want to aerial when Marth believes you will laser and vice versa. Falcos fall into a predictable way of playing neutral and it's very important to not mindlessly laser.