Please read full guide before voting or commenting guide. This is the way I play Olaf and for me it works pefect :). My opinion is that Olaf is not a good tank(after all he doesn't even have a tank tag), but he is a hell of a tough dps and very stong jungler and 1v1 champion. In this build im maximizing his dps but sacrificing some of his survability. Some Olafs jungle with smite, for me that is just a sacrife of a precious summoner spell. I found that Exhaust is more important then a blue buff at the start. And Smite sucks at late game. Why to steal someones buff with Smite when you can just kill him and get the buff you want. With exhaust u have aditional slow + dmg reduction when 1v1. :)
I see that most players run Olaf as hp stacking tank with Atma's Impaler after the Vicious Strikes nerf for me that build is not longer viable - it's very slow, you dont do that much dmg until late game + if you want to play as a tank, there are many way better tanks than Olaf(like Amumu; Malphite; Shen etc.)

If you prefer to not beeing squishy and play Olaf as tank and not do dmg or you prefer playing with smite than this guide is not for you!!!

Abilities:

Berzerker Rage:

For each 1% of health missing, Olaf's attack speed is increased by 1%.

This is what makes u awesome jungler. Plus at low health u become very dangerous when you activate Vicious Strikes.

Undertow:

Olaf throws an axe to a target location, dealing 50/90/130/170/210 (+0.5 per attack damage) physical damage to units it passes through and slowing them by 24/28/32/36/40% for 2.5 seconds.
If Olaf picks up the axe, the ability's cooldown is reduced by 6 seconds.
Cooldown 10 seconds | Cost 55/60/65/70/75 mana | Range 1000

I max this 1st because it's good for chasing with the refreshing cd. And it deals hell amount of dmg now that it deals physical dmg(armor pen). It needs a little practice though, but its easy to learn and when you learn how to use it properly it pwns.

Vicious Strikes:

For 6 seconds, Olaf's attack damage is increased by 7/14/21/28/35 base damage plus 1% of his max health. While active, Olaf gains 9/12/15/18 / 21% lifesteal and spell vamp.
Cost 40/45/50/55/60 mana

This is the second thing that makes u great jungler. it gives alot of dmg and lifesteal. And dont forget the spell vamp it works nice with Undertow and Reckless Swing always use it when initiating in fight! I get this only twice at lvl 1 and 3 for the lifesteal after I get Wriggle's Lantern I use it only for the additional dmg.

Reckless Swing:

Olaf deals 100/160/220/280/340 true damage to his target and inflicts 40/64/88/112/136 true damage to himself.
Cost 50 mana | Range 325

This ability is crazy it tears apart squishies as well as tanks. And its also spammable. Note that using Ragnarok can greatly reduce the damage taken from Reckless Swing. I max this spell second because I prefer Undertow more for the slow. Dont be afraid to spam, you lose hp, but when you lose hp you gain attack speed from passive.

Ragnarok:

Active: For 5/6.5/8 seconds, Olaf is immune to disables and reduces incoming damage by 20/30 /40.
Passive: Olaf has 10/20/30 increased armor penetration.
Cost 100/75/50 mana | Range 400

OK very useful ability it gives u passive armor pen which is very important for u. And also make u immune to disables which means use it whit Ghost and u are uncatchable! + it has very nice cd. Learn it whenever u can!

Here are some of my stats:with this build: :)

Peace and Love!

Pros:

• Really good Jungler(even without Smite) and an awesome ganker!
  
• Very good chaser with Undertow
  
• Very dangerous at low health with Berzerker Rage and Vicious Strikes
  
• Very good vs tanks with Reckless Swing and the armor pen u have.
  
• Almost uncatchable with Ragnarok + Ghost.
  
• Can eat squishes in seconds.
  
• Has the best emotions in game!

Cons:

• Very vulnerable (with this build).
  
• Not very good for teamfights (my opinion).
  
• Rather slow without Ghost

9xGreater Mark of DesolationGreater Mark of Desolation - Olaf need as much armor pen as he can get, to deal more dmg!

9x Greater Seal of Evasion - It helps jungling and vs melee heroes. If you dont like dodge or the dodge system another option is using Greater Seal of Alacrity, it will make your jungle a bit faster.


9x Greater Glyph of Focus - I choose this for more Vicious Strikes spam at the beginning and more Reckless Swing at late game and often Ragnarok usage.

3xGreater Quintessence of DesolationGreater Quintessence of Desolation - More armor pen = more dmg. If u have problem with jungling u can use Greater Quintessence of Fortitude.

About Masteries - its pretty much a standard 21/0/9 build.
- You will ask why I put only 2 point in Lethality in Offense, the reason is that I prefer the starting bonus dmg from Brute Force and you don't really have that much crit chance only 3% from masteries and 15% from Youmuu's Ghostblade which is not that great.
- I don't take Archaic Knowledge because none of Olaf's spells deal magic dmg.
- In utility i get Perseverence for better regen of mana and hp and Haste for faster ghost, then i take Awareness for faster jungling and Utility Mastery for better buff duration every jungler needs this.
- If you don't feel comfort playing on utility you can go defensive with Nimbleness for more survability, but I prefer the more exp and the longer buff duration.

Exhaust - I like this spell for 2 reasons 1st its additional slow which helps you to gank in early game 2nd the dmg reduction helps you a lot vs melee carries like Warwick. 3rd you can escape from a tricky gank with it.

Ghost - Very good for chasing and/ or escaping. My opinion is that every jungler needs it. Also it work very good with Ragnarok.

Optional Summoner Spells:

Smite - Most Olafs get Smite when jungling.Why choose Smite if you only need it before level 5? When you first port back with 700 Gold, you can get Blue and Red with an ease.

Ignite - Its an option if u want more dmg. But I prefer Exhaust (already said why). You can pick it up if your team lacks Ignite.

Fortify - You can take it on place of Exhaust if your rune build is not finished and you have hard time jungling in early game. It's a great spell through it saves towers and punishes those silly tower divers(note that Fortify now gives a assist when an enemy is killed)

Core:

Ok so I will now explain why I choose this items:

Wriggle's Lantern - This item is great for early games it provides dmg, armor, lifesteal, the proc chance for monsters and the free ward!

Youmuu's Ghostblade - This item is perfect for Olaf it gives you armor pen, which is very important for Olaf, it also gives you dmg, crit chance, cooldown reduction and last the not lesat the awesome Active which is like a little Highlander!

Berserker's Greaves - I use these because the build lacks attack speed in the early/mid game.

Frozen Mallet size - This provides some survability, and lets u gank without Red buff. Very good for chasing.

The Black Cleaver - This gives you dmg, attack speed, and armor reduction - The perfect item for Olaf.

Madred's Bloodrazor - The last item is up to you but i like Bloodrazor, because it fixes the issue with the attack speed, gives armor and dmg too + the awesome passive with which u can rip tanks with ease!

Item Sequence:

Start with 5 Health Potion and a Cloth Armor. That's a standard jungle start so there is nothing much to explain. Build Madred's Razors as soon you have 700 gold. After that buy a Boots Of Speed for little movement boost. Now build Madred's Razors into a Wriggle's Lantern - with this the jungle becomes peace of cake. Now get Berserker's Greaves for a little attack speed. Now build The Brutalizer. Then build Phage for the slow chance and the little hp and dmg. After that finish your Youmuu's Ghostblade. These are the items you need to start owning. When you have money finish the Frozen Mallet - it shuts these annoying punks that try to run away fro you. When its possible buy a B. F. Sword and build it into a The Black Cleaver. And if the game is not finished yet build a Madred's Bloodrazor.

Situational Items:

- Somentimes when the oppositing team have many hp stackers and tanks I skip Wriggle's Lantern and go straight for Madred's Bloodrazor.
- If you get targeted too much by casters just go for Banshee's Veil.
- IF the enemy team is heavy AD and you feel squishy build a Randuin's Omen or Atma's Impaler
- If the games go for too long and you have finished your core drop Wriggle's Lantern and make The Bloodthirster and switch Berserker's Greaves for Phantom Dancer.
- And if you are doing very good and the opponents are failing its very good to make Sword Of The Occult(its little risky though)

Why is it better to jungle than laning:

• Nobody knows that you are Jungling at start and in Loading Screen(beacause you dont have Smite)
  
• You wont be ganked beacuse you are not going to blue.
  
• You wont get killed in the laning phase for sure.
  
• You have 3 solo high exp lanes for your Team.
  
• You can gank everyone and you should!
  
• You can slaugahater almost every other jungle because u have a bonus summoner spell!
  

Jungle Route:

- Start off with your wolves.(a tip hit the big one once let him take some of your hp and then activate Vicious Strikes, and when they drop about 50 more of your hp active the 1st hp potion then just finish the little wolves.
- Then continue by attacking your big wraith activate Vicious Strikes and again when they drop about 100 hp active 2nd hp potion and finish the little wolves while you spam whenever you can.
- You should be lvl 2 by now learn Undertow head to your golems, kill them and activate the third potion.
- If there is a gank possibility take it!
- From now on there are 2 routes depending on the enemy:
- If the enemy don't have a jungler go to enemy wraiths kill them as normal then take the golems the same way as before and then make the wolves, wraith golems rotation in your jungle until you have 700g, when you have them go back to base and buy Madred's Razors
- If they have a jungler go to your wolves(dont worry if they haven't spawned, they will spawn in 5-10 seconds)
- Now repeat wraiths and golems rotation until you have 700 gold, then go back and buy Madred's Razors.
- Now everything becomes simple, you can take both buffs with an ease, gank if there is a possibility, if no take both buffs and gank mid or the solo lane.
- When you have Wriggle's Lantern you can get dragon easily(note that Wriggle's Lantern proc's trigger the lifesteal which heals you hard).

-Another thing that ive been doing recently in ranked with my mates is that they help me get blue first, i get bonus exp and infinite mana it works perfectly and the jungle becomes even easier, so who the **** needs Smite ? But if u are not a gambler just and dont want for you and your teammates to be ganked just stick to the regular route.

Wards and Lantern:

A good jungler buys wards whenever he has remaining money, buying wards provides vision to key locations for you and your teammates and will protect you from getting ganked in the jungle and you team from getting ganked from the oppositing jungler. You should consider that with Wriggle's Lantern you will always have 1 free ward. If I'm killing the dragon I usually put the ward in the bush near dragon to protect myself from gank from the mid champion. Even if I dont kill it a ward it so you can gank the opposite jungler. (For more good ward spots check Panglot's guide about wards) .

Team fights:

- Your job is to be "anti-carry" - this means you must target and kill the enemy carries is possible. In team fights just use Ragnarok and chop the squishies heads off.

Ganking and Tips:

- When you are a jungler you can gank everywhere. Use it! But dont run into towers, known your limits! I found that a gank in the mid early really help you and your mid champion and it will slow their solo much. Another awesome gank place is the the double lane it will provide in the worse case a waste of Flash for the opponents or in the best case a double kill and an early tower kill which will be a serious advantage. If you take some kill early you will become very dangerous later on.
- Another thing is good to always gank with red buff and with Ghost if possible it increases your gank capability by a lot.
- Keep in mind that the best champions to gank (especially in mid) are the squishy ones that don't have without a decent escape mechanism, or without F;ashFlash good champions to gank: Anivia(just try to avoid her stun); Annie(a piece of cake just try to gank her when she hasn't stacked her passive); Ashe(just use you Ragnarok); Heimerdinger(try to avoid the blind); Fiddlesticks(the fear can be a problem); Karma; Karthus(personal favourite xD); Katarina; Kog'Maw(his passive can be little tricky); Lux(just try to dodge her cage); Malzahar; Soraka; Pantheon; Twisted Fate; Twitch(try to kill him before he becomes invisible)
- This is how a typical early gank looks like - use your Ghost use Exhaust on the target you want to kill use Vicious Strikes, and start auto attacking them, then land a sure Undertow ( Vicious Strikes increases it's dmg) and spam Reckless Swing whenever its possible and he should be done already. But if he use Flash or somehow escapes dont tower dive or something, just continue with you jungle.
- When there ain't ganks just keep feeding yourself in the jungle, you need a lot of creeps.
- Sometimes its better to fight than running away, because with Berzerker Rage + Vicious Strikes + Youmuu's Ghostblade you can become very powerful 1v1 and rip your opponents apart. But know yours limits, even Vikings run away from time to time, and you need to know what you can take down and what you cant.
- After a gank you can push very hard with the combination of Wriggle's Lantern proc effect its awesome for massive creep waves + Vicious Strikes you are pushing as hell + armor pen works on turrets!.
- Another good thing to do is to cover the lanes, when your solo need to go back to shop, so the exp from the lane won't be lost and also you will defend the tower.
- Keep in mind that Ragnarok + Ghost + Youmuu's Ghostblade + Undertow spam = great escape mechanism with which you become pretty much uncatchable!

So i've played few games with him in TT and i can say he is a very good ganker and a strong carry(and anti carry). And with his massive creep potential he can grab buffs after he grabs Madred's Razors with an ease.

Thats pretty much everything. I hope you like it I'm open for suggestions. And if you down vote pls tell me why :). You can post stats so i can know how it works for you. Now go and chop their heads off!

AND Remember:

Beware of The Techno Viking!