Attaching a card to its current Top-Most Card will not have any effect.
§ 434.1.g Core Rules PDF (officieel)
§ 434 Attach
§ 434.1 Attaching is the act of linking two cards on the board together to combine their effects in some way. This causes one or more cards to become Attached and at least one card to become a Top-Most Card. See rule 716. Attachment for more information.
