Been playing the little guy since before the patch and now that he's finally caught up in power, he's considered OP. Here are a couple champs that destroy me as Kog, hope it helps:
Akali - Smoke nullifies BAB, dash and gank. I'm consistently owned by her.
Vladimir - Life drain, blood pool counters BAB, ult has a nasty habit of killing you when there is no one near to explode on.
Malphite - Here is one tank you are not going to take down with BAB, his slows are insane.
Kennen - Lightning ball nullfies BAB, kills Kog insanely too fast with his combo/stun
Trynd/Xin - Both kill Kog faster than BAB can kill them. Endless Rage nullifies it too, Xin's knock up interrupts it.
Kassadin - If he gets the jump and silences, might as well start planning your bomb route.
Warwick - Have yet to 1v1 and win against Warwick, even fully geared, esp. if he's eschewed HP gear for mitigation since that just makes his heals that much better.
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