When you find out that Jhin can achieve 1000 AD...

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He can get to around 700 AD late game with a build that is actually good (so not stacking 5 IE's and a BT).

I've seen him running around with over 1000 thanks to an AP Janna with Ardent Censer.

http://www.quickmeme.com/img/9a/9a32b5fd2e96017c9d8f02162b2fb06caaa83327da49a61274dcba6af038d7d3.jpg

EDIT: If you want to check out his scaling and calculate the damage with 1000 AD check out Jhin's LoL Wikia page. Some of those scaling numbers on the abilities are scary.

EDIT 2: http://www.quickmeme.com/img/e2/e2494b2dae9d4c537141a47eaad0913f6732f4839e20513804ad74f4fa7d28be.jpg

Jhin with 1079 Attack Damage and largest crit of 3741...