My first guide on this site, not going to spend a lot of time and detail making this post super fancy, just going to explain my playstyle/build for Olaf as I've been playing him a lot in ranked games recently with great success.

My rune page is standard for every champion I top on, I choose the quints for a little extra damage because I almost always pick up defensive items, armor pen is standard for most every ad champion. Dodge runes really make a huge difference when combined with Nimbleness, they allow you to go toe-to-toe with whoever you are against and will help you chase/escape early in the lane when you need to. I take MR/level because you almost always are farming for the late game at top and won't need flat MR.

I really love the defense masteries I have selected, the extra armor/mr helps a decent amount in the early levels, and the Strength of Spirit talent will give an extra 5-6 hp/5 depending on your champion, which boosts your flat regen to around 15/5 with no extra items, a great pickup for Olaf with the build I'm using. The offense masteries are standard, I prefer +4 damage to creeps over 1% cdr because while they are both almost negligible differences, I prefer the last hit assistance early on.

Cloth 5 is one of the strongest item openings if you are going vs a physical top lane (GP, Talon, Riven, Lee Sin, etc). It will give you about an extra 10% damage reduction and if your opponent doesn't have any armor boosts it will really give you an edge and allow you to trade harass and come out ahead, giving you lane dominance early on. Cloth armor transitions nicely into Wriggles Lantern, probably the best item for any AD top. It gives no only lane sustain through lifesteal, armor, damage, and the ability to push your lane quickly when your opponent shops, but a free ward that can potentially allow you to stay in the lane until you are around 3000 gold or so assuming you are doing well.

For boots, Berserker Greaves are standard, as it's the only source of Attack Speed I get in my standard build, and I will only take Merc Treads if I am against a hero like Fiddle/Morgana, or a team with a lot of disable, or 3/4 heavy magic dealing champions.

Frozen Mallet will be the first core item you will want to build, it is superior to Warmog's in every way if you are looking for an hp-boosting item. It gives you damage, a slow (so your ranged ad can take red), and you only trade it for 500 or so HP and a little hp regen. Follow up with an Atmas and you will be sitting really beefy around level 16, a huge threat and a huge tank to boot.

Grab a Guardian Angel next, as it will give you a nice boost to armor to support your ~2700 hp pool, increasing your effective health dramatically, and increasing your Magic Resistance to about 50% before penetration.

You will be around 180 armor and 100 MR at 18 at this point, you can choose to build a FoN/Banshee if their casters are strong, or choose to be riskier and go for a Phantom Dancer, giving you amazing carry potential at the cost of survivability. Olaf is damage dealing champ but in my mind he is first and foremost a tanky initiator who can charge in, pop his ultimate and send the enemy team running scared while he focuses their carry before his ult ends.

My build will vary from most Olaf builds in that I do not take Undertow until the other 2 skills are maxed out. I simply do not need it nor do I have the mana to support using it. I have never had an issue getting a kill due to not having a slow, as ghost/nimbleness + exhaust is more than enough to chase.

I have a video you watch to further understand the play style this skill build entails, in the next chapter.

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