Let's ignore everything
We've already seen a shift towards completely ignoring armor, what with the introduction of Conqueror, change to IE, and buffs to LW items. We've got champions that ignore turret targeting, champions that ignore cc, champions that ignore death. Now we're getting one that ignores True Sight.
Let's take it a step further and add defenses that ignore true damage.
but its USUALLY insignificant.
….ap 
and very situationally
(e on massive low hp minion wave in middle of a fight) are the exceptions, and one of them is ult use only..
is a good runner up to those champs cause he doesn't rely on damage reduction like
or
he relies on a shield that makes everyone ignore him for 3 seconds.