One Piece Card Game

You pay costs by resting (turning sideways) the required number of active DON!! cards in your Cost area, not by discarding them (Official Rule Manual p10).

A [Blocker] is activated by resting that card during the Block Step, and it takes the place of the card being attacked; Blocker activation explicitly requires you to rest the blocking card (Comprehensive Rules p16; Official Rule Manual p11).

When a Character that has been given DON!! card(s) leaves the field (e.g., is K.O.'d or returned to hand), the attached DON!! card(s) return to the Cost area and are set to the rested state (Official Rule Manual p16).

When damage causes a Life card to be added to your hand, you may reveal that Life card and activate its [Trigger] instead of adding it to your hand; Trigger activation happens at that point during the Damage Step (Comprehensive Rules p17; Comprehensive Rules p24).

No—Characters are normally unable to attack the turn they are played unless they have a keyword that allows it (e.g., [Rush] or [Rush: Character]), which specifically permits attacking that turn (Official Rule Manual p11; Comprehensive Rules p24).

If both players have simultaneous effects, the player whose turn it is activates and resolves their effects first, then the other player activates theirs; if a single card has multiple simultaneous effects, its controller chooses the order (Official Rule Manual p16).