Hey, nice to meet you here:

welcome to this guide.
Sorry, in the past I created a guide with a similar name for the same character. Alas it was too updated and I learn much in the time. I was thinking to update it, but I decided it's so different I created a new one.

Here we go.

Warwick is an evergreen and a character usually playable in ranked. Currently I saw him banned only very few times.
He's realiable, he's fun and he's a jungler.

Yep. One of the main roles of the dear wolf is Jungling.
The second role of Wawick is gank enemies, and cuts enemies fleeing routes (BTW: trying to not kill steal :p).

He is also extremely good in solo-laning and I like him in 3 vs 3 matches. So in this guide I'll add also a section for laning Warwick.

BTW: He's extremely good at laning solo top, and one of the best champion at 3 vs 3. In that case, avoid Smite and take Exhaust. (and use the second build template)

In this guide I will show my point of view, and ask you to check if you can suggest me any improvements.

6.sep.11 - Update item progression. I still leave Madred's Razor as first item to complete if you jungle. But I set the Madred's Bloodrazor after the Guardian Angel. No need to rush to Bloodrazor. You can gank without Bloodrazor, relying on damage made by teammates. On the other hand, Guardian Angel is very useful in early teamfights.
If you still want to damage, I suggest to use other items, such as Wit's End, since the unique power of the Bloodrazor is more useful in mid/late game.
6.sep.11 - added a chapter "how to counter enemies". Mordekaiser, Tryndamere, Jax. If you want my opinion on others just ask.
24.sep.11 Patch update. No change on ww (a change on Mordekaiser, so you will find more easy to kill him).
I changed the Quintessence from Greater Quintessence of Health to Greater Quintessence of Desolation.

Pros:
- Reliable. Easy to learn, challenging to master.
- Good and safe jungler. He can jungle without going low health.
- Lasting: he heals on hit and with Hungering Strike, so he need to return home fewer time.
- Early Dragon Killer! (both on 3vs3 and in 5vs5)
- Very nice ganker.
- Suppress and damage is useful also in teamfights.
- You are a good chaser. (If they run it's more fun.)
- Early Dragon Killer! Especially in the twisted treeline (3vs3).
- Nasty in 1v1.

Cons:
- Poor escape mechanism: Timing and positioning are very important, flash can save you, but not always. Also your ulti can flash you out of combat, but hey, this is the last choice, and usually it will be on CD.
- Short ranged. Only the ulti is long ranged. And it takes you in the middle of the enemy. So you can't fight from a safe place.
- Not an early ganker. Warwick can gank very well starting from the 6 level, with his ulti. Before he lacks stuns and slows.
- Jungle is safe usually, but there's the risk to remain low level: if you try and fail an early gank (it happens) or if you got counterjungled in early game you can grow slowly.
- Smite almost wasted on late game. (But continue to spam it on minions! If you're lucky you can even steal baron.)
- Fear the Ignite! Vulnerable to Ignite, since this spell reduces healing from Hungering Strike. When you got ignite flee is a good choice!
- No AoE, making group encounters difficult, and a little slower than other junglers in early game jungling
- Hungering Strike spends much mana in early game. (Take the blue buff or use HR wisely).
- First enemy target in mid game.
- Troll target. If you jungle and the game go bad often low elo will blame the jungler. Also some mid elo do it.
- One turret down. Sometimes, if the solo top is against 2 and these 2 are good enough (especially if they are both ranged and the solo top hasn't heal) they can harass your teammate. The top tower can go down! Tell him to deal with it (and don't blame the solo top). Tell him to chill and play safe. A tower down is not so bad, especially if you can do at least 2 ganks. It worths the tower.
BTW, usually it doesn't happen.

Runes can make the difference, choose it wisely.

My runes:

Greater Mark of Desolation Greater Quintessence of Desolation

Why?
Greater Mark of Desolation is the best mark to improve damage; it stacks nicely with the ulti; and it's good for jungling.
Greater Seal of Evasion. Dodging is really useful in every fights, it helps you avoid damage; and, best of all, it's useful against the creep in the jungle.
More: it's very useful against other junglers you may meet. They all need to rely on normal attacks, dodging them is better then armor. And with nimbleness it may grant you also movement speed.
Greater Glyph of Cooldown Reduction. Your ulti will refresh quicker, and also hungering strike. Why not? Having Hungering Strike ready 0.2 seconds before can save your life.
Greater Quintessence of Desolation. Some armor penetration, useful against creep and in against enemy in early game. Not bad also for mid/late game.

I think there are no other good choices for Marks, Glyphs and Seals.
Speed? No way. ArP is better.
Mana? You have enough of it, it isn't so vital. And if you really need it take the blue buff. (usually at 7 level I don't need it anymore and I help ap characters to take it)
Gold? I don't need so many gold.
Health? I have it with the quintessence and I regenerate with my attaks, that's enough.
Armor or Magic Resistence? In the jungle Dodge is a good defense. But if you prefer Armor given by Greater Mark of Armor go with it. Alas this doesn't stack with Nimbleness
Crits? If you want the critical strike you should seek another build. Although CS stacks nicely with the ulti I think it's more a Jax thing, or a Tryndamere, Gp. I'll leave it to them.

Another choice is:
Greater Glyph of Scaling Cooldown Reduction. It grant you more CD reduction on late game. It can be a choice.
I prefer Greater Glyph of Cooldown Reduction since it's better than Celerity until 11 level. And it can change early combats.

I chose Greater Quintessence of Desolation, but there are other choices for quintessences:
Greater Quintessence of Cooldown Reduction
Having Hungering Strike ready can save you life, even if it refresh 0.2 seconds quicker. Have I already tell that? It's nice also for the ulti.

Greater Quintessence of Movement Speed
Some movement speed never hurts, you will pass much time running after fleeing enemies, or moving in the jungle.

Greater Quintessence of Scaling Cooldown Reduction
As I said dodge is very useful in the jungle.

Greater Quintessence of Health
Health is generic and always useful in early game. Not so good in mid and late game.

Defense:
Hardiness is a must for jungle safely since it crants early armor.
Nimbleness and Evasion are extremely good. Since dodge is useful too. And Nibleness is a nice advantage in chasing or fleeing.

Offense or Utility?
I know. People like to go 21 in one of them. But for ww jungling is best to have both.
The main elements are:
Utility Mastery Absolutely. More time buffed.
Awareness can give you a boost to arrive quicker at 6. At sixth you start ganks.
Archaic Knowledge With this mastery you can do more damage with the Hungering Strike. This means that you heal more!
Plentiful Bounty Not so bad. And since its better than the other choices.

A big trouble: Sunder or Offensive mastery?
Offensive Mastery grants you the best advantage on minions. And it make you a quicker jungler.
Sunder : good against minion. Not so much as Offensive mastery. But Sunder helps you also against enemies. So I choose it. But also Offensive mastery is a good choice.

Why not Alacrity ?
Attack speed is good. But Archaic Knowledge is better: more damage with HR and so more heal too.

Why not go 21 on utility tree?
Since I want Nimbleness , and also some point in Sunder .
If I go on 21 on utility I can't have both.
BTW: Intelligence and Quickness are extra good. Blink of an Eye is good.
Presence of the Master not so good for Warick, so I suggest to avoid it.

But I still prefer Sunder , Nimbleness and Archaic Knowledge .
If you really want you can go 1/9/20.
That's another viable choice, nice both for ganks and jungle.

Other two option are:
0/21/9 - Too defensive. You don't need so much defence. It can be useful, but you have to delete Archaic Knowledge that grant you heal and Sunder . It's a choice, but not my favourite.

9/21/0 or 21/9/0. I'd say not. They're not so bad. But I don't like delete the utility tree.
Utility Mastery is useful even in late game. And Awareness grant you quicker levelling in jungle. Remember, the more quick you arrive at sixth level, the more quick will be the ganks.

9/0/21 or 21/0/9. The worst. Why?
You can change maybe Evasion and Nimbleness but you can't avoid Hardiness .
You need armor for jungle.

21/9/0

Easy here.
If you lane I prefer the offensive mastery. I avoid critical boost since I prefer to have sure source damage. I don't like to depend on luck.

If you want a more tanky char you can go also 9/21/0. I'd say it depend on the team.

I prefer Hardiness , Nimbleness and Evasion than utility Awareness since Warwick is usually on the solo lane. So he already level quick on lane. And I prefer to zone the enemy early.
(What does it mean zone? -> I'll explain later.)

This is the passive. it grants you some healing on every hit, and it stacks 3 times. Useful, both in lane and in jungle.


HR is the first choice since it grants a nice amount of damage with and a good healing source.
Use it to farm creep in the jungle, and to eat enemy champions.


You need HC in the beginning to farm more easily. After that it will be useful lately in teamfights and to destroy turrets faster.
That's my second choice.


BS can be used to follow fleeing enemies. But it shows you also enemy junglers with low HP, so you can track and gank them down.

* I prefer Hunters Call than Blood Scent since I prefer to play a fighter and help in early team fight.
If you prefer to play ww as an assassin is better Blood Scent, or mix the two abilities while you level up.
** In this case remember that Blood Scent stacks nicely with Boots of Swiftness


That's a master piece to gank down enemies, just choose the right moment and place to use it.
Be nasty.
- If you outnumber the enemy start with it, block the squishiest enemy and gank them with your friends.
- If you're one vs one try to challenge the enemy; if he fights back start with HR, and use the ulti only if you go low on HP or to stop fleeing enemies. If you plan to start a 1 vs 1 fight try to use ID it as last resource, don't start with it if you can.
- In group fights attack the weaker, the injured or the squishiest. You can use the ulti to start the fight or to dive in.
- On special occasion you can use it also to tower dive and kill an injured enemy: ID, then quickly HR, then flee is recommended.
- An enemy is attacking you (or one friend of yours) under your turret -> use ID against him, he will take damage from both you and the turret. That's very bad, for him.
- Attack when you see that your teammates can focus the enemy.
- Care of enemy stuns, wait the use them before attacking with Infinite Duress.
- Care of Cleanse and Quicksilver Sash, since they can free the opponent from suppression. Care also of enemy skills such as Remove Scurvy of Gangplank, that have the same effect.

Warwick will jungle. Everywhere. And he will never go low health.

5 vs 5 map.

Phase One (Level 1-3): let's settle
Blue is optional.
Bold green is mandatory.
- Kill the big wolf on 1:40.
- Leave the little wolves and on 1:55 go to the blue buff - drink one health potion + use Smite (remember the mid to pull the golem before engaging).
Ok now. 2 options.
1) They have don't the jungler! (Hey. It happens. Very often on normal, almost never in ranked.)
You can stole their jungle. This is all optional.
- Kill their banhsees (one heal pot) -> check for mid gank
- Stole their red (1 heal pot + smite), leaving a minion
- Stole their golems (don't leave golems, kill them both)-> check for gank. If there's the chance to gank drink the other potion. Oterwise
- go back to steal their banshee (smite + leave one banshee alive)
- shop, or go to your banshee and golems if you have not yet 1050 golds.
Then.
- stole their blue
- stole their wolves
- check for ganks.
Remember. If you enter their jungle you need to know the best escape routes, where and how to use flash, since they can try to gank you.

2) They have a jungler.
After the blue golem.
- Use another another heal pot, to be safe. Then go to their banshees! Try to stole the big one. Or all of them. if the enemy comes check his hp. Then fight or flee, but remember that the enemy mid laner can be near.
- Go to your banshee (spare the smite for the red buff, if needed use one heal pot).
- Red buff (smite+heal pot).
- Check for ganks.
- Go to two golems.
- Return to banshees and clear them with a quick smite on the bigger.
- shop or continue with wolves and golems.

Shop
When you reach 1050 gold run and buy the Madred's Razor and Boots. If you've more golds buy wards.
Time to enter in jungle phase 2.

TIPS, Phase 1:
Cover!: the blue golem can be stolen, and they can even kill you when you are low hp. Ask your friend to come and cover you, especially if the enemy has no jungler. If they are on skype remember them to continue check you on the blue golem, is the more dangerous moment, since is the only time when Warwick go to half health and become vulnerable.
Pull: after some initial scouting you may ask one other player to attack the blue golem and go away, so the golem chase him and you will have some free time to attack. This will save you an health pot.
BTW: Usually players will pull the golem without needing to ask.

Jump the wolves: The creeps near the blue golem are wolves like you!
No. That's not the motivation. You will xp quicker if you avoid them at first levels. The gold+xp/timespent doesn't worth enough on the first route. When you return after the little golems, or when you've the razor, feel free to kill them. Xp and gold will remain low, but you will be super fast.

Prepare for gank:
Remember you team mates to stay def. If they stay def there are more gank chances.
I know that's a common rule. But it's better to remind them.

Early game gank?
Warwick is not an early ganker. He hasn't stuns nor slows. So go gank only if you're sure of it and the enemy is really low. otherwise jungle and grow xp! You need to arrive at 6 as soon as possible.

Cover if needed
Sometimes you need to cover some lane. Check also your teammates health. If they are too low suggest them to go base and heal while you cover.
Commor rule: When you cover DON'T STEAL XP! Do only last hits to enemy minions. For newbye: that's mean that you don't attack minion, but you only hit them when they are low hp, so you kill them and gain golds.
Exception: If the enemy hero is dead push the minions. Attack them, even use Hunters Call and maybe also Hungering Strike. Push your minion under enemy turret so they die -> less xp for the enemy.

That's the early game. If you succeed in the gank you will have the same level of the solo laner. Otherwise you will be a level higher of the double laners, or maybe the same of them.

Phase Two(Level 4-7): time for buffs
Now you have the Mardred's Razor. Time to use it. Go direct against the Lizard and take Red Buff. After this search for Gank opportunities. If you find any go and kill.
Otherwise go and try to stole their Blue Golem Buff.
- Be nasty: when you stole their blu golem kill only the golem. Leave the two creeps. So the enemies won't have anymore the buff and need to kill the creep to wait the respawn (do the same with the red lizard).
Continue to run around and search for ganks, on your free time you may farm the Red Lizard, the Blue Golem and the little golems. Take out the banshee only if you are waiting for a gank in the middle.
Avoid the wolves, again! They're again too time consuming now. If you have some free time take out only the wolf group of the enemies. Stealing from enemies is always a nice habit.
Early dragon! From 5 level you can attack the dragon, but only if you have one allied champion with you.
When you start the dragon remember that ww have to attack first!
You can even attack the dragon alone if you already have both blue and red buff. I tried it and I did.
But I suggest to avoid it unless you're extremely sure of your safety, and your full of hp and mana.
You will go extremely low on hp if you try alone the dragon at 5, even at 6 is very dangerous.

TIPS, phase 2:
Play safe. If you see too much enemies around avoid attacking dragon or entering in their jungle at this level.
Ward!: Use wards.
- No enemy jungler? Put wards between the lanes. Best spots: in the lonely bush between the lane. Or in front of the dragon.
- They have a jungler? Put wards in their jungle. Best spot: in the bush of the blue golem.
Smite is wise Save the smite for the last hit, to avoid that enemy stole the buffs or the dragon.

Phase Three(Level 8-15): steal gank steal gank steal
Ok. Now the jungle is yours.
Attack the buffs and the creeps. If you feel safe enough it's much better to steal enemies creep.
Dragon control! You can do the dragon alone, even at half health.
If you are full health you can fight the dragons even if the enemy jungler is around (not if he's another ww or Udyr or other badass jungler, and not if he is of higher level). When the enemy jungler come stop attacking the dragon and attack the enemy, you can win sometimes since you heal.
Be care: if the enemy has smite remember to play safe, they can steal the dragon, and that's very bad.
Map control: buy and use wards to check where are the enemies, especially the enemy jungler.

Phase Four(Level 16-18): Baron, you're mine
Continue like phase 3, and you can also try the baron.
Never try alone, you will surely die.
But you can manage the Baron if you have one allied champion with you, and I mean ONLY ONE. Especially if he's ranged, or do loads of damage.
I succeeded 2 vs the baron. I tried at 17 level with Le Blanc, 18 level with Master Yi and 17 level with Vayne and 16 with Miss Fortune.
Remember again: ww has to attack first and use the smite to do the last hit!

Take the rythm
Jungle creep will respawn after a bit. Try to check the time so to optimize the jungle routes and mix them with ganks and lane cover.
Here the spawining time.
Dragon initial spawn: 2.30
Dragon respawn: 6 mins.

Blue and red buff.
Initial spawn: 1.55.
Respawn: 5 mins.

Banshee, wolves and two golems.
Initial spawn: 1.40.
Respawn: 1 min 40 sec.

And BTW.
Nashor.
Initial spawn: 15.00.
Respawn: 7 mins.

GANK
Yup.
Train yourself to check the map always. Look who is pushing who is under the turret, and who is low hp.
When you see a good chance. Go for it.

Early ganks
Make early ganks only if you're sure of them, or if your teammate needs urgenly your help (such if the enemy zone him out -> I'll explain later what mean the tactic "to zone").
In early game the main issue is to arrive at sixth level! So xp has priority.

Don't rush things.
How many hp have you? How many hp have your teammates? If you or them are below half health avoid ganks! Tell them you will cover the lane while they go heal.
If they insist, try to check more deeply and find out if it is a good time for gank. If not tell them to chill out and go heal.

Ping!
When you gank ping the target.
Or target the opponent pinged by your team.
I know, I know. It's so obvious. But sometimes happens that your teammate isn't aware of you.
In normal (and I think also in low elo) happens. More than you expect...
So ping. Just to be sure.

Respect the flame.
Who got the ignite? Check him on loading screen!
Before a gank or a team fight check if they used it. If they have it. Play safe!

Gank who can't flee
An enemy didn't have the flash? Check it on loading screen!
Has he already used the flash or the ghost?
Select him as the main target.

Check for enemy wards
Your team mates could know about enemy wards. Ask them if the lane is warded.

Wards and map control
A jungle will run all around the map. So you're the best player to put wards between lanes or even behind enemy lines.
Buy them! A Ward can change a game. More you put more it's likely you will win.
Remember also that you, as a jungler needs to know enemy position to avoid their ganks.

Warwick is an awesome character for laning. He can make damage and also heal himself.

I start with Boots and 3 Health Potion.
The boots help me to harass the enemy. Run and flee to damage him.
Why?

To zone the enemy!

ZONE tactic.
Tactic description: Threat the enemy and push him out of minion fight. So the enemy will get no xp.
How to do it?
- Last hit the minion. Don't push them. Only last hit! It even grants you more gold.
- Harass the enemy. Run to him, Hungering Strike on him, then attack. If he stays use also Hunters Call. If you go too low hp. RUN AWAY and heal.
- Heal yourself. Use Hungering Strike on enemy champion mainly. But if you're too injured use it on minions too. If enemy minions are under your turret stop the "Last hit" and attack them to heal with the Eternal Thirst.
- Health potion wise. Right when the fight begin, if the enemy stays and engage: use a potion! Sometimes the enemy didn't see it, it will be an advange for you: unexpected healing.
- Hide in bushes. Especially if the enemy has ranged attacks. In the bush they can't target you. And they will always fear to come near.
- PUSH HIM AWAY. If you did all of it soon the enemy will be at half health. You will be much more healthy. So he will have to avoid you. And you can push him away from minions. NO xp for him! You will win.
- Don't chase. Except when you're sure to kill. Grow xp and stay safe. If you zoned him out of the xp you will kill him soon.
- Care for ganks. They will come soon (unless you're against a noob team). A zoned enemy is a extremely handicap for them. So they will send there someone to gank you down, or, at least, to do you enough damage to stop zoning the opponent.
- Care of minion damage. At low levels minions can change a fight. And if you attack the enemy they will attack you. Take care.
- BTW check enemy spells, as usual.

On the first shop I usually buy the Ninja Tabi since they're better than Marded's Razor in laning. They're cheaper, they grant you more movement speed, more armor, more dodge... and so they activate more Nibmleness, so more movement speed again.
You can take other items, based on your opponent. For example I buy fast some magic protection if I'm against annie or other ap chars.

In the twisted treeline try to take the top lane. use the build for the solo top, so masteries 21/9/0 and Exhaust + Flash as spells.
There you can zoning the opponent (like in the 5vs5 solo top).

And take care of this:
On 5 level you can do the dragon more easily. And often enemies don't check the dragon so early.

So take the Madred's Razor soon, ask you teammate to cover your lane and go dragon.
To be more safe and more quick you can wait 6 or 7, or maybe take some buffs before.

In 3 vs 3 sometime it can happen that you push too much and you arrive at the enemy tower.
Don't stay there.
Go in the jungle, kill some minions and return in the lane when they push.
Then try again to zone the enemy.

When you're fed enough go bot and try some ganks.

Wawrwick tend to be an attractive target. Ww need to be near the enemy to fight, ww isn't a tank, ww can do damage and, lastly ww can heal with the HR.
Enemies know that, so they tend to attack you very often, and kill you, the quicker the better.

That's why you have the guardian angel.
You can enter in the fight right after the tank (try to stay near him). Often the enemy will target you.
Try to resist as much time as you can. Use HR against the nearest enemy (better if he's squishy too, but not mandatory, you need the HP granted from HR).
If the enemies aren't noob they will kill you, but if your ally aren't noobs the enemy will have one or two casualties too.
That's good.
You'll revive, so we have 4 choice.
- The battle is won -> follow and finish fleeing enemies.
- The battle lost -> try to flee or at least kill as many enemies as you can. If you still have the ulti you may use it to teleport away from your enemies.
- The battle continues and you are no more the target -> attack the squishy and the fleeing enemies.
- The battle continues and you are still the target -> HR and flee, if they follow continue running, if they don't follow strike back.

Remember to use your ultimate wisely.
-> at start, blocking one of the more powerful enemies.
-> after revive, to finish one enemy and regain some health
-> against fleeing ones... as always.

Oh, BTW, sometimes the enemies see the Guardian Angel and ignores you. No problem. Go through their lines and eat their casters, or make them flee.

Core:

That's a must in many games. Damage, speed, armor, and a nice unique ability.
If you Jungle I suggest to take as soon as possibile the Madred's Razor, but there's no rush to arrive at Madred's Bloodrazor. You can take them as third or even fourth.

If you jungle and you need more map control and you plan to build tank you can take
Wriggle's Lantern. It's cheaper.
Remember to use also wards! The more you control the map the better.
* Madred's Bloodrazor are mandatory if one or more enemy champion is an HP barrel. Such as Singed or Cho Gath.

Very important:

Yeah. I chose Ninja Tabi since:
- They are cost-effective: cheap and realiable.
- They give you both armor and dodge. Both useful in jungle fights.
* If I'm in lane a take Ninja Tabi before the Madred's Razor.


Why this?
I suggest to take it just after Ninja Tabi.
It's reliable, it defend from both magic and AD, and it grants you a second chance.
Remember that you should be one of the main enemy targets!

Why before Madred's Bloodrazor?
Since you don't need so much damage at the beginning. It's better to rely on your team mates. You suppress, they kill.
Teamplay.

If enemy relies mainly on Magic damage I suggest to take Spirit Visage instead of Guardian Angel.

Interesting, but replaceable

Cost effective. Some damage and some defense together.
If you aren't earning enough gold I suggest to buy Wit's End before Madred's Bloodrazor, since Wit's End is cheaper.
You can avoid Wit's End, especially if you aren't target of Magic Damage.


Some Attack Speed is welcome. Ability power too. But the important thing is the unique ability: if you use your ulti with this item equipped you will crash away 24 magic resistance from your target. Very nice for your Hungering strike. And so much useful if the enemy is targeted by your allied casters.

Completely repleacable... but I had to chose a sixth item.

How to make happy all your group, and granting them some bonus, and also some life stealing? Take the Stark's Fervor!
Noob advice: to take only if the other team member didn't have it.

Situational

Oracle it's useful against stealthy champs, and, to avoid ganks it's mandatory against Evelyn and Twitch (and other champions who can wander in the jungle under stealth).
With the oracle will be really easy to kill Evelyn and Twitch if you meet them.

Item order, and other suggestion.

First and second items

First item to take is the Cloth Armor, and two Health Potions Health Potion, you need that for jungling.
As soon as you get 1050 golds recall and buy Madred's Razor and Boots, with them you will jungle so much better and quicker.
Then I choose the Ninja Tabi, other choices are:
Mercury's Treads. You need these ones if you see too many casters within the enemy, also if you see many stunners.
Berserker's Greaves. If you want to be super aggressive, but I prefer defense. And, if you really want to be aggressive I suggest Sorcerer's Shoes since they grant you a better Hungering Strike, and HR is better than Attack Speed.
Boots of Swiftness? I'd say no. You don't need that much movement, you already have nimbleness and Blood Scent, and also an ulti that teleport you to the target. That's enough.
Come on. Some of your team will surely stun or slow the enemy. Movement speed is not a main element for warwick.

Third item

Guardian Angel.
Warwick can use some defense. And istant rebirth can change entire games.

Fourth item

As fourth item I chose the "cost effective" Wit's End.
Other good cheap choices are:
Offensive
Sword of the Divine grants you attack speed, extra damage and armor penetration. This object becomes mandatory if you see enemies with dodge, a must against Jax.

Last Whisper. Enemies with too much armor? Take this and solve the problem. (it gives also damage!)

Defensive
Spirit Visage. If you need quick magic resistance that's your choice. This grants you some cooldown. Great. And it even boosts the heal. It's so lovely.

I prefer an offensive one, since the third gives defence.

Back to the second

After the fourth items return to the second and finish Madred's Bloodrazor.

Last items

I chose Malady since it stacks with the ulti and Zeke's Harbinger just to show my team play attitude ;).

And there are other good choices. You can use the cheap items I listed before, and also:
Offense:
Bloodthirster grants damage and life stealing. Remember to fill its stacks with minion kills. If you take this avoid Zeke's Harbinger.
Hextech Gunblade. Life stealing, damage and ability power, with a nice unique ability that make more damage and slow the target. If you take this avoid Zeke's Harbinger. Maybe avoid also Frozen Mallet. Since they both slows the target.
Black Cleaver. To cut through enemies with high Armor.

Mixed:
Frozen Mallet. HP, some damage, and a nice unique power that slows your target. Not bad.

Defense:
Banshee's Veil. Magic resistence, mana, health and a good unique ability.
Sunfire Aegis. Only if you plan to stay in the middle of the fight, so remember to stack the sunfire cape with other defensive items.
Thornmail. Only, and I repeat only, if your enemies damage come from attack damage (AD char like trynda Gangplank, Ashe, etc).
Randuin’s Omen. If your team don't have a tank and you need one take this.
Force of Nature. Are you taking too much magic damage? And I mean really too much. Take this (after Spirit Visage). It grants also some movement speed.
Quicksilver Sash. Mandatory if enemy has too many stuns.

1 - Best Spells

JUNGLING SPELL
Duhn duhn DUHN.
The main thing that no one liked on the first guide.
I changed my mind.
Now I suggest to take smite.

- It makes you jungle faster and safer.
- It makes more sure the buffs from stealing.
- With Plentiful Bounty it even grants you some more gold.
For now I never saw a high helo jungler without smite. So I settle and accept it as the best tactic.

LANING SPELL

With this you can slow the target.
You can also use it to gain advantage in the first fights, and it helps you to strike down enemy hp and start zoning.
It can even use that spare point to arrive at 4 in offensive masteries.
I think that Exhaust can be more useful than Ignite. You can take improve Cripple to improve smite so your attacks will hurt more, especially in the beginning.
Exhaust is also useful for chase and it can even help you to flee.

FLASH FOR BOTH LANE AND JUNGLE

It can be used to chase.
It can be used to flee.
It can be used to gank.
That's enough. It saves your life, and kills enemy.

2 - Very good spells


Good enough. You can take it instead of Flash.
It grants you the same thing. A little better at chasing, a little worst for ganks and flee.


Some damage, and it halves enemy healing. Not bad in some situation.
* If your team mates have only Exhaust take it.


Why not. You gank on top, then teleport and gank bot. Often they don't expect that.

3 - Not so good, not so bad spells


I don't know. It stacks with your ulti, and it could be used also in jungle.
I prefer Ignite and Exhaust, but if you feel creative that can be a choice.


Fortify is always welcome.


You already have enough heal. But hey, sometime the heal saves your life.

Clairvoynce
Ok. If you jungle you can use some map control. But this is usually a spell for support chars, not for junglers.

4 - Almost bad spells


Have the enemies so many stuns?
I prefer Quicksilver Sash, but Cleanse can be useful. Sometime.

5 - Spell to avoid


This is a spell for magewick.


Troll!

Here some enemies and how to counter them on the lane.
Jax.
- Buy the Sword of the Divine.
- Attack him. His attacks grow stronger when he progress (especially if he has Guinsoo's Rageblade). Every hit set him more poerwful.
So when you are at half health use Infinite Duress. Their attack return basics, and he need again to boost them with new hits.

Tryndamere.
- Stop him farming: stole his jungle and zone him away from minions.
- If it's a ranked you can see him and take Ignite if needed. Wait he use the Undying Rage run away if you can, or change opponent. After 4 sec use Ignite on him.
- If he's fleeing and you have the Infinite Duress use it.
- Buy a Zhonya Hourglass. (alas poor tactic with warwick, better one if you use magewick).
- Ask you teammates to stun him.
- Tryndamere need to push minion. This help you to ZONE him.

Mordekaiser
Hey. This is hard. But he isn't too hard.
- Fight him away from minions!
ZONE HIM.
He need to push minions. If you can set him half health you can continue to heal, then go behind the minions and start threatening him. If he can't spam Siphon of Destruction on minions you will be way much more powerful than him.
He have no CC and you can heal! So if needed you can even flee.
* Take care to not waste mana, since he doesn't need it.

Sorry for any mistyping or other errors.
Any feedback, opinions and suggestions are welcome.