So I decided to crunch the numbers on Viktor using 570 AP, with and without Lich bane.

The basis for this is landing all abilities and every tick of his ult. Not counting repeated abilities nor the shield value.

Difference's in damage:

Live Q without Lich = 832

PBE Q without Lich = 753

Live Q deals more damage by 79

Live Q with Lich = 1,194

PBE Q with Lich = 1,115

Live Q deals more damage by 79

Live E = 880

PBE E = 1018

PBE E deals more damage by 138

Live R = 2,217

PBE R = 2,611

PBE R deals more damage by 394

Viktor's full combo landing all ticks in his ult without Lich Bane Live = 3,929

Viktor's Full combo Landing all ticks in his ult without Lich Bane PBE = 4,382

Viktor's full combo landing all ticks in his ult with Lich Bane Live = 4,291

Viktor's full combo landing all ticks in his ult with Lich Bane PBE = 4,744

Tl;Dr- PBE Viktor out damages Live Viktor by 453

However, with the 1.25 second delay, Live Viktor does more dmg by 49 if Aftershock fails to hit someone.

EDIT: I feel as though my title might be a bit misleading. I'm not using the numbers as a case to say PBE viktor is better, I had been seeing a lot of people say this was a nerf to his damage, so I decided to do the math