I think we need a version of thornmail for spells

Literally what I said in title, when you get hit by a spell or magic damage reflect some damage to enemies, that will be much more effective against spammers like cassiopeia than "adaptive helm i die 2 seconds later because she shot 50 E per second anyway so 20% reduced damage for same spell is not so big of a deal"

Or if reflecting like 50 damage for 500 you take per spell seems unfair, at least rework adaptive helm and add griverous wound on enemies that hit you with magic damage and slow them for a second. (those effect are on thormail tho just to make it clear)

I can't remember a single time someone acutally build adaptive helm against champions like Vlad, Cass or so on, that item is literally decent (not good) only against Teemo, when obv was designed to help against all mages that just spam spells, but for whatever reason is only working on one champion and not even on that really good, you just have a extra second or two to kill him and maybe not die from poison.

Right now without a doubt the only good magic resist items are Spirit Visage and Wit's End (and wit's end is not good for his mr stats tho, just for his on-hit part, same with spirit visage)