ap is barely viable now

Magic resist is so much easier for any ad champion to build that armor is for ap armor pen is linked into normal ad items while to get magic resist you most likely have to build outside of your normal build to get cdr is also hard to get and not on useful items executioners calling is 800 gold while morreicon is 2800 hexdrinker is probably 3 times more gold efficient than seekers armgaurd and provides a sheild there is no duskblade equivalent aside from maybe liadrys which CANNOT kill a champion because it works by current health and not total health

basically if the enemy is building magic resist you are useless in damage while all you can build in return is an hourglass