Literally help top lane out and deal with your bs Riot. 
Is in no possible way a fair champion at the time. At all. Darius, Riven, Garen, Fiora, Olaf, Sion, you name it, he counters it. Wtf is a free shield every 4 seconds? Wtf is a spammable low cost executing q. Help us top laners out and deal with your mess. Thank you.
Well he is made to counter lane bullies like those u listed. But compared to them, he has bad late game.
Pantheon is meant to punish those late game damage dealers who want to not build tanky as their first item. If you pick someone like Sion or Garen and go straight into armor you've essentially shut Panth down - he'll run out of mana before he can poke you down now that he doesn't get to buy 5 mana pots every time he goes back, and no the refillable ones are not enough.
All Counters to him.
Also, I don't know why you said Darius, Darius poops on Pantheon.
