A couple of seasons before it wasn't that big of a deal because the MR items (apart from Force of Nature) didn't have such a high MR. Meanwhile Ap Champs have exactly 3 Options, which are not even all that optional anymore...well as long as you want to deal damage to anyone with more than 50 MR. Then we have Ad Champs who even have a choice in their % Penetration items AND 3 Flat Penetration items.
Tl:Dr
Mr is too strong and Armor too weak.
Huh? Mag pen is hands down better than armor pen. First, Void is just night and day better than the LW items. 40% total pen on Void compared to 35% bonus pen on the LW items. Even with the extra damage on LDR it still isn't as effective Void would be against a tank. Let alone LDR bring practically useless against squishy champs. As far as flat pen, you can get 33 flat m pen for 2600g which is less than a single 18 Lethality item. Not only that, but Lethality is gated by level which means you don't even get the full 18 pen until level 18.
In my opinion I'm feeling the exact opposite. I feel like the only decent MR item is Adaptive Helm only because the passive. Building armor feels much more effective
So adcs are mandatory.
You know the whole "Lethality Meta" thing people like to complain about? Well imagine if we had the same amount of penetration items for Mages.
"Magic Pen Meta QQ"
Honestly though, noone would build anything but magic pen items because AP is so scarce and takes alot to actually get anything meaningful out of whereas Magic Pen just straight amplifies your damage by an absolute ton.
This argument doesn't work against Lethality and AD's because AD's have far more viable options in the item build routes they wish to go down (such as health/AD items and Crit items).
Some mages are balanced around having high base damages and lower scaling to incentivize them to build CDR over raw AP (
, 
, 
, 
).
However, with magic pen this whole dynamic no longer exists since they can just build Magic Pen and do just as much damage as the higher scaling AP champions and would probably just be the better champions.
Hell, 's best builds already involve building m.pen items/flat damage bonuses (
) over raw ap items after CDR since he doesn't scale as well with AP as he does with penetration.
Same goes for , and .
AP just needs better itemization in general in terms of new unique AP items. What they don't need is more flat pen to abuse and create a M.Pen meta with.
One mr item +1-2 hp items = I can basically never kill said person until full build unless I'm playing something like Malzahar.
Adc's just deal much more damage than APC's, and Riot balanced that out by making armor items stronger than MR, and yet they still feel weaker. They even made pen items much better in magical over phsyical. Yet those also feel weaker.
And then people might wonder why Corki, who's never been any good in the lategame before his changes, is actually becoming insane in lategame, just because he has crit itemization directly translated into magic damage.
MR is stronger, but there's also far less of it available, so it has to be more powerful point-per-point, because you just can't reliably stack as much.
To me it only FEELS like that because ADCs output the same amount of damage each basic attack as a mage does with an ability, and since adcs get to basic attack you upwards of 2 times a second they shred you regardless of how much armor you build.
*Change randuins crit reduction to 90% Kappa
Probably because as you said, there are more armor pen items then magic pen.
[{quoted}](name=Nuclear Waifu ,realm=EUW,application-id=3ErqAdtq,discussion-id=QsRpXc0O,comment-id=,timestamp=2017-12-21T13:45:21.098+0000)
A couple of seasons before it wasn't that big of a deal because the MR items (apart from Force of Nature) didn't have such a high MR. Meanwhile Ap Champs have exactly 3 Options, which are not even all that optional anymore...well as long as you want to deal damage to anyone with more than 50 MR. Then we have Ad Champs who even have a choice in their % Penetration items AND 3 Flat Penetration items.
Tl:Dr
Mr is too strong and Armor too weak.
And not just that but also look at the damage types. AP usually comes in the form of burst damage, and AD not only is universal in that all champs do AD damage but also most champs specialize in AD damage.
