Originally Posted by Enzo Gorlomi
Okay, looks like this might have been totally my mistake. I haven't encountered morde much, never 1v1 against him, so I didn't know how his passive worked.
I was exclusively using my double-up/make-it-rain against him (my usual routine against other ranged AD's), looks like that might not have been a good idea *facepalm*
The best way to deal with him as MF is to autoattack him the second you see him in the lane, and aggressively zone him out. His spells don't hit hard until he levels up some, so he can't generate enough shield to block you from beating the snot out of him. Meanwhile you're levelling faster and earning more money than him and keep the pressure applied the whole way. He's only scary when he hits 6 (and only if you let him harrass you a lot).
You can use Double Up as he retreats out of autoattack range for the extra damage, and Impure Shots debuff will help stop him regenerating properly between waves.