Not only AP itemization is inferior to AD, but Sorcery runes too.

So apparently, most Mages have a lower winrate when running Sorcery keystones. Listing: Azir, Karma, Lissandra, Vel'Koz, Ahri, Annie, Ryze, Vladimir, Kennen, Brand, Veigar, Heimerdinger, Zyra, Zoe, Karthus, Elise, Anivia, Malzahar, Viktor. Each of these champions have a different Keystone (usually Summoner Specialist or Electrocute) that simply outclasses any Sorcery keystone.

Now, this would be fine if Thunderlord wasn't specifically gutted and turned into "Electrocute" to make it less usable for mages (aka 3-unique-attacks, since mages have the clunkiest autoattacks and it's pretty hard to fit in autoattacks as a mage, especially later into the game), so in order to proc it as a mage you'd normally have to hit your full combo.

This would also be fine if we were taking a look on one specific champion; maybe they're very flash-reliant for their combos like Annie or Vlad so Summoner Specialist would be very effective on them, or maybe that's a mage like Ahri that has a relatively easy time proccing Electrocute thanks to her Charm.

But no, the vast majority of Mages use a non-Sorcery keystone more efficiently than a rune path that was specifically designed for Mages - or rather, spell-casters; but clearly Mages are the primary spell-casters in the game, and they have the least synergy with other rune paths from all roles, yet they somehow use other Keystones more efficiently.

##My only conclusion is that Sorcery Keystones are simply worse than others, rather than "other Keystones have a better synergy with X champion's kit".

######Obviously, staight buffing Sorcery keystones will also make other roles able to abuse them too, and I do have a few ideas in mind on how to make them more mage (or rather, spell-caster) -specific, but that's slightly off-topic and suggestions are usually overlooked anyway so nvm that.

Edit: I mean Keystones dammit, not the whole rune path. I actually think the Sorcery runes themselves are pretty good.

Edit 2: A lot of the arguments I see here claim that "Comet is so good on X champions, everyone is taking it" or "X champions abuse Aery and it's the best with them". I never said otherwise. My whole point is that mages are left behind with no Keystones that fit them properly, while other roles seem to be using whatever they want. Even if the Sorcery keystones were made more spellcaster-specific and consequently better for mages, other roles will still have other Keystones to fall on that fit them like a glove.