Abyssal Scepter + Kayle
So, just jumped on the PBE and tried the rework of Abyssal Scepter with Kayle. Rushed Nashor's, grabbed boots, and then got Abyssal.....I really must say that the way the item and Kayle's passive work in tandem is truly disgustingly evil. Galio Bot, 138 MR, walked into my bush....Q E auto auto auto, dead. His MR went as follows: 138. Abyssal Proc'd, reduced by 5% down to 131.1 (keeping decimals for now). Q hit, 3% reduced, 126.96. 3 autos, 9% more, 114.54, another AS proc, 5% more down the drain, 100.74. At this point, he was down to half health and had only gotten his Q and one auto on me. Another proc and another auto brought his MR down to a pitiful 96.6 and a quarter health, and then a wild Rengar appeared to ks. But thats besides the point.
The point is, with the range on Abyssal Scepter being just slightly shorter, like maybe 25 units radius shorter, than Kayle's Autoattacks with Righteous Fury activated, the wombo combo in total reduces an enemy's MR by 45%, and if she grabs a Wit's End like she is supposed to, that is another 25 MR gone. So with only 2 items, Kayle can take 100 MR, take 25 and then reduce it by 45%, leaving 41.25 with just 5 autoattacks. If she gets pen boots and void staff, she ignores 15 of the 41.25, leaving 26.25, ignoring another 35% after, so with 3 items and boots, the enemy is left with 17.06 effective mr against Kayle, not something anyone wants to be dealing with.
Basically what I am saying is that right now, I think that abyssal Scepter changing from 20 flat to up to 30 percent REDUCTION may be too powerful. I know for a fact that mage assassins with gap closers like Ahri, Kassadin, Ekko, Kayle, Evelynn, and quite a few others with short range are going to see a huge spike in power, and survivability by purchasing this item.
They already brought it down from 45 to 30, but I think the main change that should occur is from percent, to flat.
....

if vs an auto-attack heavy team.