Game mode: Opposite day, AP and AD item reversal through adaptive stats (maybe next april fools),
So the following stats could be reversed
AP and AD, by the adaptive force system
Mpen and Lethality
% pen
MR and Armor swapped
All things that would deal physical deal magic, and reversed
Examples
400 hp
67 AP
20% cdr
Dealing Magic damage to an enemy cleaves them reducing their magic resist by 4 % stacking up to 6 times
Dealing magic damage to an enemy increases movement speed
48 AD instead of 80 AP
Active scales with AD and deals physical damage
This could be fun
maybe do some things with spell damage vs auto attack damage for triggers?

MR swapped to Armor Instead of On hit, it'd be spells deal
Armor swapped to MR
instead of on being hit with autos, it'd be on being hit by ailities

ADC finally
I can be tanky and take your but like mages already do

as top lane fighter.

or 
