How to make Marksmen or ADCs bot lane's autos be reduced to 44% effectiveness or less easily.

Just buy + any armor item which at most costs 2.9k gold. Which in total costs 4k gold. For 4k gold you can easily reduce all Adc's autos to 44% by the mid game regardless of their items.

Example math:

ADC does 100 damage ninja tabi reduces it to 88 before armor applies then lets take a tank like shen that goes top lane and is level 11 around mid game normally. Lets take his base armor of 51.3 armor+ 30 armor from ninja and another 50 from an item like sunfire cape and lets include the mastery that pierces 7% of total armor so that gives us a total of 122 armor. Now lets add armor in. So 88* 100/(100+122) = 39.6 damage but lets round it up to make it 40 damage meaning you just reduced an adcs damage by 60% with only 2 items for 4k gold!

With these 2 items you basically made their ADC damage highly ineffective against you until 8.6k gold 2x the amount of gold you spent on armor.