Miss Fortune with both Last Whisper and Void Staff

Not all that worth it since building straight AD is better on her due to the power of impure shots.

I'm a bit of a newb but i like this build and triforce on aram. You've gotta go ad on summoners rift though like the above post says.

Maximun Penetration ( ͡° ͜ʖ ͡°)

Nah. You only ever do 25-30% of your damage as magic damage, and that percentage decreases as the game goes on. Better to take stats that scale with each other like AD, AS and crit instead of taking a stat that enhances the lower part of your damage. If she did more magic damage in the later stages of the game, then maybe.

It's a possible item, but there are much better choices.

(I did build Zhonya's Hourglass as ADC MF once because the enemy had so much engage+mobility. Although I was also obscenely fed, so figures.)