How do you counter insta kill ultimates in the midlane?
I always take
against champions like
because i know post 6 there's not much counterplay against their KO combos, is there something i'm doing wrong? or is it just pure unfairness that I can outplay them but still get destroyed when
just presses R to kill me.

there you go. This guys ult works exactly like Yasuo's wind wall. Even if you see it hit him he can still ult and negate the damage from it.
E or severely reduce it at least like
and POOF ... the dreaded mage dies cuz he almost cant kill anyone 1v1 cuz CD and no sustain.
or any ADC mid for an easy cheese/snowball against any Mage right from level 1 and u wont have to worry about counterpaly later against a dumpstered enemy.