This is sort of like pin the tail on the donkey but the donkey isn't supposed to know.
On buying your drink at the paticipating pub, you are handed some star stickers. The kind we all used to get for memorising the 12 times table. Of course any small highly visible sticker or tag could be used.
The
object, over the course of the night, is to place the markers on the other patrons without their knowledge. My theory being, the dunker you are, the less aware and the more accumulation of brightly coloured touches you will face.
There are no points but getting stars on the face or areas where the person is too drunk to notice is the ultimate aim.
Eventually, the star struck drinking groups will be wisked away by taxi as they are barred service because their drunkiness is plainly seen on their face.
Highway Policeman: 'Sir, are you sure you haven't been drinking?'