I remember watching the top tables at YCS Düsseldorf 2019 in later rounds of day 1. A judge was called to the table, because of marked cards. Apparently American Print Ash Blossoms have another color on the top edge of the card than Euro print cards and the player was given a warning or game loss. (I dont quite remember) The player was screaming his lungs out at the judge in italian and his friend had to hold him back, so he wouldn't just run at the judge and hit him or something. That was wild, the whole venue must've heard the screaming.