I was playing Eve, went against a full tank Shyvana, right? So early game I usually get a leash and go invade their jungler and kill them at their buff. By the time I reached Shyvana, she had already downed her red, and was killing the little guys. She had ~150 HP, so I thought I'd just kill her anyway... yeah. That's what I thought. After chasing her for a good 3 seconds, I did maybe 80 of her 150 HP, despite hitting her with my E and a few Q casts. Then, she heals up and finds me at mid lane, and with NO AD OR AP AT ALL, and nearly kills me with a few autos. Eventually, she would just chase me around instantly killing me, and there was not a thing I could do. I couldn't kite her, I couldn't fight her (and she is still going full tank + Cinderhulk, not one bit of AD), I couldn't jungle, I couldn't do anything. The entire enemy team was a bunch of AA spammers and Annie, so they'd just click on me and I'd instantly die.
But seriously, Shyvana was the worst of them all. Invincible, yet out-damages everyone but our ADC. Full tank, yet hits for over 500 with one attack.