OMG THIS IS SO OP
Tanks are OP! They can survive anything! Assassins are OP! They kill me before I can react! Bruisers are OP! They are too tanky to kill and have too much damage! ADCs are OP! They deal way to much damage in late game! Mage supports are OP! They deal too much damage with no items! Supporty supports are OP! They have too much utility!
Maybe insert champion, class, or role here is OP because it got ahead in your games because people don't know how to play around it.