Eru

Idk, maybe it might be luck, bc i only have wing scarf to farm boxes and i find them kinda often (i farmed around 1 hour today and i got 4 2019 boxes and 1 2018). As gms said, apparently wing scarf's drop rate chance is lower compared to the latent ones, so in my point of view it doesn't seem that low. But then again i might just be lucky...