Olaf has low health clears in the early game. Usually he start his Blue Sentinel at 1:40 and will be on his Red Brambleback around 2:30. Unless you're low ELO, in which case he'll probably be on his Gromp instead. Anyway, Invade his Red at about 2:15-2:20 if you play a strong early game jungler like Lee Sin, Elise, Shaco, or Kha'Zix and he should be an easy kill. If you're not a strong early game jungler, such as Hecarim or Zac, invade his Red after your first camp and take it, then take is Ancient Krug but leave the smaller one and the ones that spawn, before returning to your jungle to clear it.
This'll leave Him at a significant experience disadvantage and rob him of his strongest early gank potential. It will also give you an early experience and level advantage, as well as double buffs. You can safely clear your jungle while Olaf is forced into a much worse clear or potentially a recall. At 7 minutes you can look to take his Blue Sentinel as it respawns.
If played for maximal clear speed, Olaf gets dangerously low on health the jungle. If you can catch him while low while doing a camp (so his ability rotation is on cooldown) you can force him to burn Ghost or Flash or die. After that just ward for your laners. He has no ability to wall hop so he has to take very standard gank paths. If he gets a lead he can be pretty beastly in Mid game, but he falls off hard late game, so if you have to, turtle and wave clear until you have enough items to kite and pop him before he does any serious damage.
You need a champion with a lot of damage and sustain. Good champions would be Nocturne, Warwick, and Xin Zhao. Or you can use a champion that can outplay him with their abilities such as Lee Sin, Yorick, Zed, Elise, Talon, Kennen, Gnar, Tryndamere, etc.
Master Yi would be great too because he isn't reliant on CC to win fights and can soak damage as well as dodge abilities. He deals damage insanely fast so he'd likely dominate an Olaf. But he likely won't win very easily until mid-late game.
If you have a skilled ADC playing a mobile adc champ then olaf should be relatively easy to kite, just dodge his axes. Ashe is great at kiting him while his ult is down.
Also if you need to CC him to kill him then for obvious reasons don't use it when he ults. Either do it before or after, how you do that is on you. A lot of people waste their CC while he has ult and then he goes on a rampage and kills them.
He's a strong duelist, but he underperforms against multiple enemies (fully single-target damage). If you're having trouble with an invading Olaf you can't fight off, ward your jungle entrances and catch him out with your nearby laners.
Very good point actually about the ult. When fighting Olaf as a melee champion it is usually best to stay around him, but out of his melee range until his ult wears off. No sense in fighting him when he has the advantage.
This'll leave Him at a significant experience disadvantage and rob him of his strongest early gank potential. It will also give you an early experience and level advantage, as well as double buffs. You can safely clear your jungle while
Master Yi would be great too because he isn't reliant on CC to win fights and can soak damage as well as dodge abilities. He deals damage insanely fast so he'd likely dominate an Olaf. But he likely won't win very easily until mid-late game.
If you have a skilled ADC playing a mobile adc champ then olaf should be relatively easy to kite, just dodge his axes. Ashe is great at kiting him while his ult is down.
Also if you need to CC him to kill him then for obvious reasons don't use it when he ults. Either do it before or after, how you do that is on you. A lot of people waste their CC while he has ult and then he goes on a rampage and kills them.
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