A Shield Counter is a counter used by the effect of "Mirror Knight Calling" in conjunction with 'Mirror Knight Tokens". They allow the tokens to prevent themselves from being destroyed by battle by removing a counter instead.
List of cards that use Shield Counters
|Japanese name||Primary type||Secondary type||Attribute||Type||Level/|
|Mirror Knight Calling||ミラーナイト・コーリング||Ritual Monster||???||???||6||0||0|