Yu-Gi-Oh! players compete in local, national or worldwide events to increase their global ranking in the Konami Digital Entertainment (KDE) standings or win valuable prize cards and cash awards. Organised play events require each player to have a Player ID card or registered COSSY number in order to participate. The COSSY ID number identifies a player in the global ranking system and appears in the upper right hand corner of the player's ID card. New players must obtain a Player ID card and number as part of registration for KDE events.
Attend a KDE-sanctioned Yu-Gi-Oh! event. Local game stores, conventions and some colleges or universities host regular events. Sanctioned event organisers process registrations for KDE.
Pay the event fee, if any, when you fill out the list of the cards in your deck for the tournament organiser or head judge. KDE requires a complete card list prior to each event to prevent the use of banned cards.
Provide the tournament organiser with your name, date of birth and city of residence. An organiser will add this information to your Player ID card.
Accept the card from the organiser or head judge. The card acts as your identification for sanctioned events, though the KDE only requires the COSSY number for entry.
Complete the COSSY registration online after the event. Registering your card confirms your details and allows organisers at other locations worldwide to access your rankings for events. Event organisers may contact firstname.lastname@example.org to obtain additional Player ID cards for upcoming KDE-sanctioned tournaments.