Magic Resist Is Disgusting Right Now and Magic Resist vs Anti-MR Itemization Needs An Overhaul
Magic Resist Itemization
AD MR Itemization:
(soon Edge of Night)
Tank MR Itemization:
Support MR Itemization:
AP MR Itemization:
On-Hit MR Itemization:
Global MR Itemization (2+ Categories):

Anti-Magic Resist Itemization

Not gonna lie, Magic Resist and Anti-Magic Resist itemization is AWFUL right now when you compare it to Armor and Anti-Armor itemization. Two of the Anti-MR items are also MR items, one is extremely niche and very reliant on another item (Rylai's + Liandry's), and another is so innately bought that it basically reduces Magic Resist for all enemies by 15 (Sorc shoes). The only remotely healthy anti-MR itemization is Void Staff, and that is ridiculous. AP has ONE remotely healthy anti-MR item! One! Riot, we need more good anti-MR itemization! Currently, we have one good one and that just isn't acceptable. Magic Penentration itemization needs just as much work as Flat Armor Pen currently does, if not more.
Abyssal Scepter
Both an anti-MR item and a MR item, which is unhealthy in itself since makes it a rush item for APvAP match-ups. In Season 7, it is being removed from the anti-MR itemization (essentially), with the Passive being changed to "Deal 10% increased magic damage in an aura" instead of "Reduce the MR of nearby units by 10-25" without ANY replacement being made. Cool, you have made Abyssal SLIGHTLY less of a rush item in APvAP lanes. However, it needs a replacement if you go this route.
Sorcerer's Shoes
This item needs to be reworked, period. Boots shouldn't provide an effect like this since it basically causes all MR to be reduced by 15 against AP users due to how often it will be built on AP users. This item makes Riot have to balance the game around every champion having 15 less MR against the vast majority of AP users, which is just not healthy for the game. Sorcerer's Shoes need to be reworked to provide a different stat and then have a new anti-MR item put in it's place that isn't so global of an item.
Wit's End
Another anti-MR item that is also an MR item, it shares a similar issue with Abyssal but not quite as extreme. It is one of the healthiest of the unhealthy anti-MR items, but it still isn't at a place that it should be. It is incredibly niche and basically makes it a ALWAYS RUSH THIS item in Magic DamageVMagic Damage teams that have an on-hit champion. It's not as huge as others here, but it could use tweaks.
Liandry's Torment
This item is so incredibly niche AND reliant on another item (Rylai's) that I honestly find it shocking it wasn't decently modified in the Mage update. It's an Anti-Tank AP item, but the way it makes itself anti-Tank makes it only useful on DoT and Multi-Hit Mages. It's simply TOO niche and needs to be changed. It has it's users and they all LOVE the item, but it's a huge shame that the ONLY PURE ANTI-TANK AP item in the game is a super niche item. I also find it ridiculous that Haunting Guise only builds into this item. I mean, really? The only flat MR Penetration AP item in the game only builds into ONE item? That just seems silly.
Now accuse me of being a Mage circlejerk fanboy all you want, but this is the truth. Look at anti-armor itemization and then look at anti-magic resist itemization. Extremely drastic difference in the number of choices available to AD champions and a lot healthier to the game overall, especially once Season 7 hits. Anti-MR itemization is just truthfully awful right now and could be expanded upon and made a lot healthier for the game.
mid game... Or anyone with just 1 defensive item really lol.