[{quoted}](name=A Miss Fortune,realm=NA,application-id=3ErqAdtq,discussion-id=Ni18X6gH,comment-id=00020000000100000000,timestamp=2015-07-11T15:14:44.589+0000)
Due to the fact that Ability Power scales higher than Attack Damage, unless you're building 6 Infinity Edges or something, late game her Q and E will do more damage, but it won't be enough.
AP Evelynn doesn't make use of a colossal attack speed buff, and since everything scales off AD anyways, her auto attacks can hit really hard. I usually build something like
. Makes her a bit tanky with mobility and great burst or chasing potential.
I don't really know why people argue AP Evelynn is really strong though, don't get me wrong it's a lot stronger than some off-meta builds, but if you had to choose between AD and AP Eve as a strong damage output, AP Eve wouldn't really ever have a higher damage output, since her Q doesn't do more damage until you hit late game, and AP Eve can't make the use out of 120% attack speed nearly as well as AD Evelynn.
Q and E does more damage with AP very early in the game.
Compare Warrior+Botrk (65 AD) vs. Runeglaive+Rabadons (229.5 AP):
Warrior+Botrk adds 65x0.7 = 45.5 damage to Q
Runeglaive+Rabadons adds 229.5x0,55 = **126.225 **damage to Q
Warrior+Botrk adds 65+~160 (2x Botrk against a target with 1000 current health) = 225 damage to E (damage is further increased by Warriors armor pen.)
Runeglaive+Rabadons adds 229.5x1.4 (1.0+0.3 from runeglaive + 2x0.05 from arcane blade) + 85 (Runeglaive base damage at Level 11) = 406.3
So Q and E does way more damage with AP. If you buy Hydra instead of Botrk, Q will do a bit more damage, but E will do way less damage. Anyway AP is way better for her Abilitys.
AD Evelynn does more damage with Autoattacks, but AP Evelynn can do the same damage faster, from higher range and while running away. AD does more damage only if you autoattack for a long time, but this is more easy to prevent for your opponents and you need more tankyness to do it. But if you buy tankyness you fall even more behind AP Eve damage-wise, what makes it very difficult to assassinate targets. AP Evelynn can kill targets very quickly, and this is the most efficient way to use her stealth.
I played AD Eve in Season 4 for a very long time, then I changed to AP and I was really surprised how strong it is. First I bough Nashors Tooth all the time, because I thought I need to have strong Autoattacks. Later I noticed that that is not even needed. Before I changed to AP Evelynn I read all these whining comments in the internet, that AP Eve was nerfed to death. These comments are always the same. But it is all bullshit. AP Eve is not even close to be dead.