What is the counterplay to Malphite's ult?
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Fast reactions
Don't stack up
What is your definition of "counterplay"?
Imo counterplay shouldn't occur in champ select, but you can Zhonyas, Flash, or build MR. We all know it's an outdated and obnoxious design tho.
Counterplay? What's that?
The whole point is that there is little counterplay you get that right? His ultimate is 95% of the champion and all of his kits power. Without it he is USELESS. Any fight that breaks out in the lategame that he doesn't have his ult for / his ult is wasted is a 4v5 as he does nothing without it. If you are having problems dealing with him in the mid game, thats where he is strong, until you get your defensive items and you can't heavily punish him for using it. He's essentially the same as an AD assassin that regard, but once you do get those defensive items, he is USELESS. Even more useless if he builds AP.
Depends on the malphite build. If he goes full tank, just kill his team after the ult. If he isn't full tank, just kill him after he ults.

Basically MR and HPs
The rest of his kit having little-to-no impact in fights.
I mean theres itemization of course, reaction time assuming you have flash/zhonyas/ability up and dont have ping over 60 lol, personally tired of all the ap malphites running around thinking they're actually good at the game though lol
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positioning.