*from a comment that i saw in Youtube.com, thanks to TVXQismywholelife *
L has the key of the Treasure Box, the key actually belongs to him
——> Sunggyu beats him to take the key
——> Sunggyu success beats L
——> Dongwoo and Sungyeol try to stop Sunggyu but both of them lost their way
——> Meanwhile Sunggyu already enter the labyrinth where the Treasure Box was hid.
——> Hoya and Woohyun success enter but Hoya lost in it. ——> Woohyun success defeat Gyu
——> Sungjong kill Woohyun
——> Sungjong steals the Treasure from L