To stop buying armor/Magic Resist. I mean as you buy more armor and magic Resist the gain becomes less and less, so when is a good point to stop buying? 60% reduction? 65?
To clarify: Tank champ, Presuming that the enemy team is mostly, if not totally composed of one damage type. (Like you are likely to encounter in Aram)
It depends on how effective your champion's utility and base damage is, and how balanced/imbalanced the damage sources coming from the other team is.
It is quite possible, if the enemy team is a single damage type, to go full tank and contribute sufficient damage (
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It's a little bit of a mix up when people saying resistance stacking is not effective after a certain point. In actuality every extra point of armor is worth the same amount of effective hp as the one before it.
It's just as you buy more resistance, health becomes more valuable, or as you buy more health, resistances become more valuable. Or even once you're tanky enough, a single damage item makes you much more combat effective in total...
If you have 1,000 hp, and a 50 damage reduction (that's 100 resistance), you have 2,000 effective hp. Double your resistance to 200 you'll have 66% damage reduction. Not as much gain right? Wrong. With a 66% damage reduction you actually have 3,000 effective hp. Going from 98% damage reduction to 99% takes a gigantic amount of extra resistance, but it's actually doubling your lifespan. It's just after a certain point buying hp or offensive power becomes a more combat effective use of your gold.
At the end of the day though the carries scale the hardest thanks to AD/crit/attack speed/and armor pen multiplying each other, so you're not forever immune...
(im assuming your talking about as a tank champ) totally depends the game against a full ad comp its never a good time to stop buying Armour unless your building a massive health item also you can build some damage if your ahead but not to much maybe two items max but if your behind you just want to stack defensive stats
