Olaf Build Guide by Arzndragon
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Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
The different types of masteries Olaf runs with best:
Almost everything in the offense tree helps Olaf clear the jungle faster and give him lots of damage early game when he starts ganking lanes. Butcher and Bladed Armor makes jungling clear at least 20 seconds faster. A must for jungling. Armor penetration and extra damage on targets below 40% is really strong.
Let's see what the offense tree provides for Olaf.
1/1 Summoner's Wrath Put a point into it for improved Ghost.
3/3 Brute Force Because Olaf does not use AP at all and extra damage is appreciated.
4/4 Alacrity 4% attack speed is helpful on Olaf and you need the 4 points for the next mastery.
1/1 Weapon Expertise 10% extra Armor Penetration. How much more armor penetration are we going to have? Simple enough, more damage output.
4/4 Deadliness Since Olaf's Undertow and Ragnarok got buffed, his damage output is insane. He no longer needs to build over 200 armor or magic resist to tank all the damage. His Undertow scaling is EXTREMELY nice now and Deadliness provides AD to this. Havoc has lost it's use and a 1.5% damage increase is not noticeable compared to having extra AD per level.
3/3 Vampirism 3% lifesteal gets you 18% lifesteal with Wriggle's Lantern since they nerfed it by 3% for that specific reason. I picked lifesteal over Deadliness is because I do not build Olaf like an all-out DPS champion. You could of course pick up a Youmuu's Ghostblade along with Atma's Impaler for some crit chance but you shouldn't build more after those 2.
3/3 Sunder 6 more armor penetration. With 9 Greater Mark of Desolations and 1 Greater Quintessence of Desolation, you have 24 armor penetration at level 1, this is enough to hit the creeps for a full amount of damage.
1/1 Executioner 6% more damage dealt to enemies below 40% health? Olaf like.
1/1 Summoner's Resolve The extra 10 gold really helps out every time you use smite because
3/3 Hardiness 6 extra armor is crucial to reduce the damage taken from jungle creeps. If you cannot afford Greater Seal of Armor yet, I recommend you spec 3 points into this mastery.
4/4 Durability For some extra health late game to scale with Vicious Strikes.
1/1 Veteran's Scars A nice flat 30 hp buff provides extra beef incase you're behind in items.
I build tank masteries on lane Olaf to provide a strong early game so he can use Reckless Swing as much as possible to dominate in his lane. It also allows him to transition to a tanky fighter late game.
Let's look through the all the masteries we use in the lane.
1/3 Resistance The slight magic resistance is helpful. The 1 point to advance further into the defense tree is put here.
3/3 Hardiness Most likely you'll be up against an enemy AD bruiser top lane. As much armor early game helps to reduce damage taken and allows you to stay in lane a bit longer.
4/4 Durability Like I said above, extra hp late game helps.
1/1 Veteran's Scars What I said above, 30 extra health early game.
2/2 Indomitable Reduced damage from any source is nice to have, especially with more armor early game to be able to trade hits with your lane opponent.
3/3 Evasion Even though 3% is a very small number, Olaf will always be in the middle of a team fight taking hits to the face no matter one. He's a melee champion and this mastery helps ease some of the damage off.
3/3 Initiator This is a very good mastery to help with ganks, chasing, etc. Great utility to do what it says. Initiate.
3/3 Honor Guard 1.5% reduced damage adds on to the ton of reduced damage taken from all sources.
1/1 Juggernaut This final defense mastery increases maximum health gained by 3% from any source and also provides 10% duration reduction of disables. Helpful when Ragnarok is on cooldown during fights.
and are the two best spells you can have for jungle Olaf.
I use ghost as my first summoner spell because you want the speed to keep up with the enemy to constantly throw axes and then be able to get into melee range so you can lock onto them with Frozen Mallet's slow. It's also an amazing escape tactic when used with Ragnarok since you can't be disabled.
Smite. Oh smite, oh smite....Why do people keep jungling without smite? I still do not know why but it irritates me when people don't bring smite to the jungle. Why do we want this spell so much?
1. Smite helps you clear the jungle faster during your first run from lvl 1-4 at blue and red buff.
2. Due to Summoner's Resolve you can catch up on gold every 70 seconds to keep up with the lanes.
3. Allows you to control EVERY jungle camp in the game. Especially Baron Nashor and Dragon.
4. Allows you to counterjungle the enemy jungler effectively.
5. Due to Vicious Strikes, you can actually heal from spell vamp off Smite which is why you want to put a point into it while jungling and this spell vamp might also save your life.
6. Allows you to control your own jungle buffs when you're being counterjungled so you can recover.
Smite should always be used because it makes everything safe while jungling and warding/controlling the map. NO MATTER WHAT, YOU SHOULD ALWAYS HAVE SMITE WHEN JUNGLING.
The only other spell I would use besides Ghost.....
The infamous flash. While it is used on almost every champion as an emergency escape mechanism, on Olaf, it doesn't provide as much utility on a champion like Olaf. He doesn't necessarily have a finishing skill. To finish off an enemy, you want to hit your axe for a gap closer, for example Reckless Swing. Take if you'd prefer but I wouldn't pick Flash over Ghost.
Any other Summoner Spells should NEVER be even thought of using on a jungle Olaf. He needs smite to control the jungle and needs ghost/flash for an escape use.
Exhaust helps you shut down enemy carries such as Tryndamere or Gangplank, or escape in a fight. Helpful in lane to beat your opponent.
This spell is meant for map control and allowing you to be in places you can't reach by only means of Teleport. It's for laning and usually top champions have it so I think it's a nice spell for solo top Olaf.
Olaf's Passive: Berzerker Rage
"Urge to kill, rising!"- Olaf
"For every 1% of his health missing, Olaf's attack speed is increased by 1%"
Why is Olaf so fast in the jungle? This is one of the two reasons that make Olaf a speed clearing jungler. His passive gives him 1% more AS as 1% of his max health drops. This can add up to more than any item in the game and more than the stats of runes and masteries combined.
His passive perfectly suits Olaf and allows him to win 1v1 fights because he can use Ragnarok at low health during a fight while lifestealing through all the damage he deals out from his increased attack speed. Perfect synergy!
This is another reason to support why I said to pick Armor Pen marks over Attack Speed reds. Why settle for 15%-26% attack speed from runes (15% with Attack Speed marks and 24% with Attack Speed marks and quintessences) when you can get 0-99% more from your passive.
Olaf's Q: Undertow
"Chicks dig my axe."- Brolaf
When Undertow is used: "Chug!"- Brolaf
Olaf throws an axe to a target location, dealing physical damage to units it passes through and slowing them for 2.5 seconds. If Olaf picks up the axe, the ability's cooldown is reduced by 4.5 seconds.
Cooldown: 8 seconds
Cost: 55 / 60 / 65 / 70 / 75 mana
Physical Damage: 80 / 90 / 130 / 170 / 260 (+1 per bonus attack damage)
Slow: 24 / 28 / 32 / 36 / 40%
This is the other reason why Olaf can jungle so fast. Throw the axe, pick it up and the cooldown gets refresh by 4.5 seconds, regardless of how much CDR you have. With 40% CDR, you can spam your axe constantly to deal insane AoE burst damage in seconds...if you have the mana for it. When grabbing blue buff, the cooldown of this skill can be from 1-2.5 seconds long. This skill can clear jungle camps very fast and any creep waves fast.
Undertow allows Olaf to gank at any time during his jungle path. It's a ranged slow before level 6 which allows him to pull off ganks earlier than Warwick, Udyr, or Nocturne because he doesn't need to be in a close/melee range to be able to use CC on a target and the axe can be repeatedly thrown over and over as long as you pick it up. It's practically a perma slow on a target if done right and you don't miss.
How to effectively use Undertow to clear jungle creeps extremely fast:
Press the Q key to aim the axe in the direction of the jungle monsters. Pull your mouse as close to Olaf as possible, while still in the direction of the creeps, until the arrow doesn't become shorter. Click down, pick it up, and repeat.
Note: If you throw Undertow into a brush, it reveals the area where the axe landed for a couple of seconds. Use this to scout an area before accidentally facechecking into the enemy team when they just dragoned/baroned.
Olaf's W: Vicious Strikes
When Vicious Strikes is used: "Brooo!"- Brolaf
For 6 seconds, Olaf's attack damage is increased by 7 / 14 / 21 / 28 / 35 base damage plus 1% of his max health. He also gains 9 / 12 / 15 / 18 / 21% lifesteal and spell vamp.
Cooldown: 12 seconds
Cost 40 / 45 / 50 / 55 / 60 mana
Why do I put a point into this skill at lvl 1 and lvl 3? Well the lifesteal isn't much since your autoattacks don't do so much damage to be able to steal large amounts of health from the jungle creeps. However, the trick to using Vicious Strikes is being able to time it so that it's up when you're about to smite the Blue Golem or Red Lizard.
Why is that? Olaf's Undertow used to do magic damage but they changed it to physical damage since it does make sense now. The spell vamp was supposed to be applied to Undertow when used. But there's a trick behind that. Smite is a summoner spell you use and is considered a spell in the game. When used, the damage from smite can be healed by the spellvamp you get from Vicious Strikes. During your first jungling path, this can heal Olaf for 40-60 health depending on your level. This trick keeps him alive and almost at full health when he's done with his jungle route.
Why didn't I put a point into Undertow at lvl 3? By repeatedly using Undertow over and over to clear jungle creeps fast, Olaf runs out of mana quickly, even with Blue buff. His base mana and mana regen isn't that high and as you put more points into Undertow, the mana cost goes up. That's why I did not invest another point into it at lvl 3. It's better to be safe and conserve your mana to be able to use Vicious Strikes whenever it's up and to heal off Smite instead of running out of mana all the time because of the constant use of Undertow.
Why did I max this skill last?
The scaling of this spell stays at 1% of your maximum health at every rank of this skill. The damage increase and lifesteal & spell vamp increase per level isn't that much and doesn't boost his damage significantly. When Olaf gets his Wriggle's Lantern, he doesn't need to rely on Vicious Strikes so much for the lifesteal/spell vamp anymore. Investing points into this skill results in a loss of lots of damage from Reckless Swing. And besides, Reckless Swing needs points to do some real damage to a single target.
However, this is the one reason why building tank items on Olaf benefits him more than other tanky dps. He gets the 1% damage scaling from his maximum health. Late game the damage increase from Vicious Strikes changes from 35 base damage to 71 damage with the full build (however, it can vary depending on what other items you build). That's almost as much damage as an Infinity Edge.
Note: Since Vicious Strikes does give more AD, Undertow does gain more damage from the 0.5 scaling. Use Undertow while Vicious Strikes is up to do more damage while you are jungling.
Olaf's E: Reckless Swing
When Reckless Swing is used: "Boom...Baby!"- Brolaf
Olaf attacks with such force that it deals true damage to his target and himself.
Cost: 40 / 64 / 88 / 112 / 136 health
Cooldown: 8 / 7 / 6 / 5 / 4 seconds
True Damage to Target: 100 / 160 / 220 / 280 / 340
This skill makes Olaf unique compared to other champions. Feast has around a 50-60 cooldown while Reckless Swing is only on a short 4 second cooldown. Like Feast, Reckless Swing can be used as a finishing skill to finish a champion before they Flash away or Shunpo. This skill ignores all resistances which means Olaf can hurt carries and tanks alike. In 1v1 fights, this is one of the reasons why Olaf can easily win. The true damage puts a hurting to the enemy champion and since it has a 4 second cooldown, it's difficult to lifesteal or spell vamp all the damage back up.
However, this skill does have a slight drawback. It deals 136 health back as recoil at rank 5. There is the use of this recoil though. You need to lower your health so you gain attack speed from Berserker Rage. Use this to enemy creeps to lower your health when you're pushing a lane to an enemy turret so you can attack more often or to whittle down your health in the jungle to clear even faster then lifesteal it back.
When NOT to use Reckless Swing: There's a benefit and downside to everything. If the enemy team can deal more damage to Olaf than he can take, Reckless Swing should not be used as a defensive resource. Lowering your health against a team that can kill you in seconds is not a smart idea. Olaf becomes stronger as he stays longer in a fight. If he's been alive in a fight for at least 15 seconds while still below 50% and lifestealing back the damage taken, your team is in big trouble. But if he dies before he can deal damage, Reckless Swing becomes useless for him.
Note: If Olaf does not have enough health to survive the recoil from Reckless Swing, he cannot use it and until he has enough health. It also applies on hit effects such as Frozen Mallet!
Olaf's R: Ragnarok
When Ragnarok is used: "Bromacia!!"- Brolaf
(Passive): Olaf has increased 10/ 20/ 30 armor penetration.
(Active): Olaf instantly removes all crowd control effects from himself. He is also immune to disables (including silences and blinds) and has increased armor and magic resist.
Cooldown: 100 seconds
Duration: 6 seconds
Cost: 100 / 75 / 50 mana
Armor and Magic Resist bonus: 30 / 45 / 60
Ragnarok is one of the best ultimates in the game for a tanky dps. If you put this on Olaf, it becomes a skill that makes him unstoppable for 6 seconds. And you thought that Irelia had CC reduction? Take a look at Ragnarok. Immunity to disables, every single one. Even though a champion is fed, the one thing that stops them is forms of CC. Olaf, however, can walk away from any CC thrown at him. You can walk past Leona and her 3 stuns with no problem. Idol of Durand? What's that gonna do on Olaf? You call that a taunt? Summon: Tibbers? An AoE stun by the use of summoning a big teddy bear is gonna stop him? I don't think so. Poor Annie.
Plus it gives a passive 30 armor penetration. 30! With this much armor penetration, you're hitting for more damage than most melee dps champions. Against carries, you'll be ignoring their armor on early levels.
The increased defense is necessary to win 1v1 fights. Using Ragnarok while he's low on health reduces incoming damage so he can lifesteal all the damage back up with the damage reduction he gets while balancing his low health with Reckless Swing. Plus, he doesn't necessarily need to build over 200 armor or magic resist just to tank damage from one major source of damage from the enemy team. Again, perfect synergy!
I've seen many other Olaf guides and playstyles and I've always seen people max their Q first. But it's my belief that Reckless Swing should be maxed over Undertow.
1. Reckless Swing is true damage and has a TON of burst on a character with little health.
2. It doesn't cost mana.
3. Undertow requires you to pick up the axe, changing your positioning. It's hard to maneuver between the target and the axe location if you've missed the throw.
Champions that build a lot of armor in lane to counter their opponent counters Undertow's damage too, which is a problem. And if you repeatedly use Undertow in the jungle or during ganks, it drains a ton of mana. You can use Reckless Swing as long as you have the health for it and it helps clear your jungle fast since it lowers your health.
You only need 1 point into Vicious Strikes because it already gives you that 1% HP to damage scaling at rank 1 and does not increase. Putting points into this spell only increases Olaf's lifesteal and damage by a very small number. You mainly want to use Smite while Vicious Strikes is active because of the spell vamp, you can actually heal a small amount from it.
Standard jungle starting items because they offer defense, the most sustain, and Cloth Armor builds into Madred's Razors.
Core Mid Game Items:
A must for DPS junglers like Olaf. It's a free ward every 3 minutes and helps you clear the jungle faster with a bit of sustain. The main reason you want it is because of the armor and damage it offers so you can take a more turret shots when diving during a gank.
Since Olaf is an off-tank, Mercury's Treads are the ideal boots since they help you survive magic damage burst early levels before you get a Force of Nature or Banshee's Veil.
Phage is nice because Olaf lacks a hard stun and relies on picking up his axe to keep slowing someone. Phage fixes this problem a bit, however it is only a % chance of the passive to proc. Eventually, you will build this item into Frozen Mallet or Trinity Force depending on what is needed.
A very helpful item early game if you fall behind. It gives health, gold per 10 to catch up in farm, and eventually you can build it into Randuin's Omen. Sometimes I even grab this if I'm ahead and I have the gold for it.
I would never buy this item if I'm behind because it doesn't give much of an offensive stat. The crit chance is only 12% and it's not what you're trying to strive for when you're behind. I would take this item if you're building as a DPS or anti-carry and will turn this item to a Youmuu's Ghostblade.
Late Game Goal:
Why did I choose this item over Warmog's Armor? If some of you may question. Frozen Mallet is extremely good if your team lacks a lot of CC. It provides a ton of health without having to farm health while also providing damage. Even though Frozen Mallet ends up being more expensive, you won't have to farm the entire health and health regen for some time to get the full benefit from Vicious Strikes and Atma's Impaler.
However, the main reason I picked this is because this build designs Olaf to become the tanky DPS of the team. Doing loads of damage while taking a ton of hits and being able to shrug it off. He can use Ragnarok to avoid the enemy team and jump to the carry and constantly slow them. The only way the enemy carry can escape is if Ragnarok's active ends, the carry has a way to jump out such as Tristana's Rocket Jump, or they can use the old fashion way, Flash. You don't always have to build Frozen Mallet on Olaf. As I've mentioned before, almost ANY item can fit Olaf and adjust his play style according to the enemy team's damage. I will go further into this in the "Builds" chapter.
It's almost bought on every tanky dps nowadays because of it's passive. 2% of all your health is converted into AD. This means stacking a lot of health and resistances which is easy to build on Olaf. Atma's also gives you some crit chance and the armor you need to survive hits by the enemy ranged AD carry. Wriggle's Lantern will NOT provide you enough armor to take a lot of physical damage. This is where Atma's comes into play. Plus, because of Vicious Strikes's passive, 3% of your max HP is actually converted into AD every time Olaf activates it.
For Laning Olaf:
Core Mid Game Items:
Other starting item choices: Doran's Blade or Doran's Shield or Boots of Speed 3x Health Potion or Regrowth Pendant if you are going to turn it into Philosopher's Stone for the gold gain or you're going to turn it into a Shurelya's Reverie.
If you've noticed, it's the same items as jungle Olaf. Why do we do this?
Mercury's Treads are obvious again. CC reduction and MR to reduce early game burst damage.
Wriggle's Lantern provides you a free ward in lane very 3 minutes so you end up spending less gold on them to constantly cover the river and prevent ganks. Again, the damage, and sustain is necessary to win the lane. Plus most solo top champions deal physical damage which is why the armor is SUPER nice.
Heart of Gold is also nice here if you're also falling behind in lane.
Late Game Goal:
Since lane Olaf builds Warmog's Armor first, he should be able to farm the passive amount to the max cap. Atma's Impaler immediately comes after because it's easily farmed and with the ton of health you gain, once you purchase this item, you can achieve 100 AD with Vicious Strikes activated while gaining 45 armor and over 1k health.
Other viable choices after core items (Alphabetically):
Aegis is a support item and is usually carried on the tank or support (duh). For Olaf, he's not played exactly as a tank support jungler, such to Rammus or Amumu. He doesn't have a strong intiation because he has no hard CC. However, Aegis of the Legion is a potential item to have on Olaf, however it isn't recommended.
This item is a popular choice among all champions because of the overall defense it provides. But what they really want is that bubble that blocks 1 spell every 45 seconds. It also benefits Olaf for the nice small amount of health it gives. It's more ideal to pick Force of Nature because of how tanky of an item it is and the fact Ragnarok ignores all CC. But as always, Ragnarok isn't always off cooldown and doesn't last forever. This is why we have Banshee's Veil for enemies like Alistar, Morgana, and Cho'Gath that have tons of CC.
This is probably the only other viable boots on Olaf. Attack speed works with his passive but that's all these boots give.
While it gives lifesteal and crit chance, it gives no damage to Olaf at all. You should almost never get this item except when I'm against SUPER heavy healing teams e.g. Soraka, Dr.Mundo or Fiddlesticks.
I would include this item as a core item but sometimes games don't last as long to be able to build this item. Why would I pick this over Banshee's Veil?
1. More MR than Banshee's Veil.
2. Insane HP regen.
3. Movement Speed.
Because Ragnarok already blocks CC for 6 seconds in fights, Force of Nature is the more ideal choice as a magic resistance item.
99 Armor with 500 extra mana and a ton of CDR. I mainly buy this item to be able to stop autoattacking champions because of it's unique passive. Combine this item with Randuin's Omen and lols at the enemy AS.
Adds both armor and magic resistance. This item is definitely helpful when you're a main damage dealer on your team and you need to survive during a fight. It also prevents focus on you and gives your team more time while you revive from Guardian Angel.
Infinity Edge is a carry item that costs a lot of money. Olaf doesn't gain much crit chance other than Atma's Impaler. It takes a while to farm for this item but will be worth it for it's stats. Too bad it sets back the rest of your build by a lot of money.
This item gives a lot of AS and deals 110 extra magic damage per 4th attack spread across 4 different targets. The extra health really helps too. Combine this with Frozen Mallet and you will constantly be proccing it's passive effect on someone.
This item should be bought when the enemy team has champions with over 200 armor that completely shuts down almost all physical damage. This is why we have Last Whisper! Increases your damage drastically against tanks.
Why is this item almost never picked anymore? Well it's expensive as hell, 3800 gold total cost. Barely any damage is given from what it offers, the attack speed is kinda nice, and the armor is actually less than Wriggle's Lantern. If you take a look at the unique passive, 4% of their health in magic damage can be severely reduced by magic resistance because its a % damage. It's not like Olaf is going to build Malady to help increase the damage on this. Not worth buying at all.
One of the newest items in LoL, it's stats are crazy. When I read the patch notes of this new item, I knew it was going to be core on Olaf. Besides the crazy 55 AD, 36 MR, the passive is what perfectly synergizes with Berserker Rage. +1 AD for every 2.5% missing health leads to a ton of AD and AS at low health. And it doesn't stop there. You gain a spell shield that soaks up magic damage which means you can be left at low health longer to take out the enemy faster. Amazing, amazing item.
A item built for defense against heavy AD champions and also provides a damage reduction. A situational item for Olaf but still a good choice. This would be the boots I'd go for if not Mercury's Treads.
I've seen this item built on many other Olaf players and I just have to completely disagree. This item gives no damage even though it gives crit chance and attack speed. Again, Olaf gains a lot of attack speed off Berserker Rage. I'd rather build that Zeal into a Trinity Force and gain even more movement speed off Force of Nature. There are better options than this item.
This item is good for champions that instastun you such as Annie. BV is better because it gives a shield and health for Olaf. But this is also another nice item to counter magic damage and CC teams.
It's the same with Force of Nature. I would include this on core items if the game would last long enough. Unlike Frozen Heart, this item gives health and health regen and 5% CDR. When you finally buy this item, MAKE SURE TO USE ITS ACTIVE DURING FIGHTS. Press R and run in the middle of the fight or to the enemy carry and press the corresponding item number key to activate it. It helps reduce and slow surrounding enemies a lot and can change the tide in a fight. Definitely a core item on Olaf if the enemy carry is fed so you can reduce their AS, which cuts their damage output during a fight.
This item should only be upgraded by Philosopher's Stone if you built it in the lane. If your support is building Aegis of the Legion or Soul Shroud instead of Shurelya's Reverie, you can be the support offtank and take this item as it gives movement speed to intiate or chase.
For the small price, it offers a lot. Health, MR, CDR, and the passive effect increases how much you lifesteal and spell vamp by 15%. Helpful and a potential item for Olaf but it's not as potential as other items for him.
Well I've been playing LoL since July 2009 and man has this item taken its toll. It used to be stackable because it didn't have a unique passive and it used to do 40 magic damage per second instead of 35 (The range of the passive is 400). I remember the good 'ol days when Garen didn't have to get some sort of DPS to be able to scale better into late game. You could just take 3 Sunfire Capes and spin to win with 120 magic damage burning around you every second. That was the real merry-go-round Garen.
Anyways, enough with the spin-to-win stuff. Sunfire Cape still a good item. It's DPS passive kinda helps with damage but because it's magic damage, it can be reduced by any source of magic resistance. The armor is only 45 compared to other choices like Randuin's Omen or Thornmail. It's up to you if you want to build this item but I don't recommend it enough to be a more "core" item on Olaf. But the health however, is VERY nice to add on him.
Similar to Infinity Edge, this is an item that would normally be on your DPS carry but it has it's uses on Olaf. The slight AD and AS boost is nice but what you're really looking for is the 45 armor shred passive that lets you hit for bonus damage (assuming the target didn't build armor items). For it's low cost as a DPS item, it's nice to have on your team since armor shred helps with the other champions on your team that also deal physical damage.
Combine this item with Wriggle's Lantern and Vicious Strikes and you have an insane amount of lifesteal on Olaf. However, the problem with this item is it's a very expensive item even though it gives a lot of offense. And it's passive stacks need to be kept up to gain the most benefit from this, which I don't think you'll be keeping up being the off-tank jungler. It's better off on your DPS Carry.
Even though it offers a ton of armor, that's really all it gives. It's passive should be the only reason you buy this. To counter heavy auto-attacking champions like Tryndamere and Ashe. However, again, like Sunfire Cape, it's passive deals magic damage and can be reduced with magic resistance items.
Ah, the infamous item made for almost every champion in the game nowadays. Why is this item good on Olaf? The Sheen proc is easy since Undertow and Reckless Swing is spammable in the jungle and lane. Phage is a nice slow when your Undertow is on cool down and the health is nice. Zeal is a small utility item that boosts Olaf's AS, crit chance, and movement speed nicely without having to waste the money on a Phantom Dancer. I'd buy this more often in games if it didn't cost 4k gold, which was the reason why I dont consider it as a core item. I recommend to buy this item while laning rather jungling since you get more cs in lane.
I find this item to be very useful when you need some defense against magic damage early game even if you have Mercury's Treads. I find it used more on champs that use on-hit items such as Warwick and Udyr. For Olaf, it's another one of those potentially good items but just not considered recommended enough to be a "situational item." If you need more MR early game, Hexdrinker is nice to have to later be turned into Maw of Malmortius.
While Riot recommends this item for Olaf, I really don't. I find it more situational than actually necessary. The stats on Youmuu's are only sub-par. But the passive effect is really nice; it adds more armor penetration with some CDR. But I really only buy this item if you need to become more an "anit-carry" than an off-tank dps. That means using Ragnarok and Ghost, if really necessary, then activating Youmuu's Ghostblade to chase down a single target that's a big threat to your team. This usually means the AP or AD carry on the enemy team. Sadly, Youmuu's Ghostblade only lasts 8 seconds max but by 8 seconds, Olaf can take out someone with the increase in attack and movement speed.
I named this chapter "Builds" for a specific reason. To show how versatile Olaf can build on any situation during a game to counter the enemy team. You'll understand what I'm trying to say below.
For Jungle Olaf:
Standard Tanky DPS Build:
Maw of Malmortius
If the game lasts to that point, this is usually my full out build. I use this full build almost all the games I play with jungle Olaf. It gives tons of health, and resistances while still having a ton of damage. Plus, activating Randuin's Omen can reduce the attack speed of the enemy team by a chunk. By looking at your team comp and the enemy team comp, and deciding you know you're going to build a Randuin's Omen, definitely get Heart of Gold after buying Wriggle's Lantern and Mercury's Treads.
"I need to get to that carry while being able to take hits" Build:
Force of Nature
I've replaced Randuin's Omen with Youmuu's Ghostblade to get the extra kick of offense to be able to get to the enemy carry while Ragnarok is active. I've also replaced Maw of Malmortius with Force of Nature for a heavier tank item.This is a successful build to take down a single target but it's not a complete anti-carry build yet because of the more bulkiness built.
"I need Armor Penetration" Build:
Maw of Malmortius