speaking of luck, I hear that right now there are some strange cults establish by jp player
for example, some group of people belive that if gacha have brightest light at background you will probably got gold servant
or some people belive in time . For example my friend having 10-roll gacha at 22:00 pm and he always get at least 1 gold servant and previously he got 2 nero and 1 nero bride when he roll 10-roll gacha at 22:00 pm