A second Noble Phantasm that can only be activated in the case his first Noble Phantasm that “never misses” supposedly fails. Derived from the anecdote in which, thinking on the case of missing the apple on his son’s head, Tell had a concealed second arrow to shoot at the evil governor Geßler. This arrow is released at the same time “it has to be shot in case the first arrow misses". In other words, it’s a Noble Phantasm that overlaps with the first arrow and exists multiple times. It will never activate in case the first arrow properly hits.
As if saying “Everyone dies if I miss the apple on my son’s head (first aim), so if it fails I must shoot the governor that gave that order (second shoot)”, it can be released deciding where to shoot it at depending on the situation. It’s possible to choose the same target as with the first shot, and will definitely pierce the target by interfering with the principle of casualty in the same way. However, it’s difficult to fire randomly because the mana consumption becomes more intense.
……Although the situation in which “the first arrow that always hits” fails is not often seen.