An attack target is a monster or player selected for an attack.
During the Battle Step, the turn player can declare an attack by targeting either an opponent's monster or the opponent themself. If a replay occurs, the turn player can select an attack target again (even if it is the same choice), potentially allowing for effects that activate upon a monster being targeted for an attack to activate again, such as that of "".
Some card effects can restrict a player's choice of attack target (such as that of "") or conduct battle with a monster without selecting it as an attack target (such as that of " "). There are also card effects that allow a player's opponent to choose their attack targets for them, such as that of " ".