Black Bug (R OP06-077)

[Main] If the number of DON!! cards on your field is equal to or less than the number on your opponent's field, place up to 1 of your opponent's Characters with a cost of 5 or less at the bottom of the owner's deck.

[Trigger] Place up to 1 of your opponent's Characters with a cost of 4 or less at the bottom of the owner's deck.
Rare
From the One Piece Card Game set Wings of the Captain