Hey guys so first thing to say is probably WHY I made this guide. I noticed that Mundo is now a champion who is being played very rarely, so I tried him again just for fun. I remembered the builds that were used like 1 year ago, but then I noticed something, that forced me to look at Mundo from an absolute other perspective: His Q skill doesn't get any bonus from your AP/AD or something else, therefore it is an AP-spell, so you will need hextech items to get profit. BUT that's not all! It deals 25% of the targets current health as damage. You guys may think "yee thats not bad, but I don't think that it is worth it to buy hextech items just for THAT...". So, how about this: On every map there are neutral creeps with a huge amount of HP (Dragon, Lizard, Golem, Nashor). If you just throw your Cleaver at them every 3 seconds WHILE having spell vamp bonus you will be healed for X (X = Infected Cleaver using cost) (The heal amount per Cleaver is about the same as the double cost of your cleaver, so for example if you have already 5 skill points on it you will be healed for 170-230(Heal you get)-90(Cost), that will end with a 500+ heal after 15 seconds. Thats why I prefer the Twisted Treeline, because if you are at the top lane you can heal yourself up using the dragon who won't even hit you once (I'll explain more about this at the chapter "ranked play"). Of course you will also get healed throwing your cleaver at normal lanecreeps but that heal amount will be about 10 hp per cleaver insted of -1/2X.

I take cooldown reduction glyphs because it is important if you use this build to spam your Cleaver as often as possible. Armor seals for defense because most champions played on the Twisted Treeline are AD Bruiser (like Lee Sin, Gangplank, Shyvanna etc). Armor penetration glyphs because at end game you will have over 300 AD in teamfights, and because you normally won't have the place for Last Whisper or Black Cleaver it is good to have at least SOME armor penetration. Health Quinteressences because you still play Mundo as an offtank and it will also give him some early game power. However if you prefer Cooldown reduction Quinteresses you may also take them because they won't be bad either.

I take 9/21/0 Masteries for him because normally after the enemies see that you get an early hextech revolver they start to think that you won't go tanky and focus you. The 21 points in Defense make sure that you have a pretty good early game and won't die too fast. And of course I take cooldown reduction/magic penetration masteries because as you may have already figured it out I am totally obsessed with cooldown reduction when I play Mundo ^^

I start with Boots and 3 pots because extra movement speed can never be bad, and I really dont like to start with Regrowth Pendant (+15 HP Regeneration every 5 seconds) because I already have high HP regeneration (Mundo's passive + HP regeneration masteries) and I go bot until I have my hextech revolver where I often get harassed by ranged enemy champions. Also I don't start with the Amplifying Tome (+20 Ability Power) because WELL it doesnt give you anything you need in early game AND you can buy just 1 pot (1 pot makes Mundo veeery sad :( so don't do it). I get then my early Hextech revolver to get free heal (problems enemy team?) so even if I get harassed or if I'm low I can heal myself up fast without using my ultimate which I prefer to use in teamfights). I proceed then with Spirit Visage or Ionian Boots to make my permaheal even stronger (that's right you can't stop mundo). After that I get Warmogs to last longer in teamfights, unless I am fed or the enemies are bad and dont focus me, then I get Hextech Gunblade as soon as possible and only then Warmogs. I continue with Trinity Force (starting with Phage, then Sheen): Phage gives me extra HP and a nice slow bonus which helps me at chasing enemies, Sheen is a sick Item for this build because with all your Cooldown Reduction and the low CD on your spells you will make a 600 basic damage hit with every second attack in a teamfight, Zeal gives you some nice movement speed and a bit more effectivness in teamfights. At last I get FoN because it gives me additional movement speed.


Spirit Visage, Warmogs Armor and Hextech Gunblade are total Must-Items for Mundo.
Other Items you may like are:
Mercury's Treads (If the enemies have a lot of CC)
Ninja Tabi (If the enemies are just ad dps champs)
Guardian Angel instead of FoN (because of the armor bonus)
A second Warmogs instead of FoN (if you think that you don't have enough hp to dive the enemies)

Items you better don't buy are:
Atmas (Low damage bonus, better buy GA)
Last Whisper (You don't need it, you already do tons of damage)
Void Staff (Same reason)
Shurelya's (It takes 1 item slot and gives only a short movement boost, but on 3v3 you have your ulti, black buffs, ghost, boots+trinity+FoN)
Ghostblade (You don't need the crit and attack speed, and you already have enough movement boosts)

You can skill your Cleaver or Masochism first, depends on the factor if you just farm and harass the most time (then skill Cleaver), or if you often participate in teamfights (Then skill Masochism)

Ghost --> OP movement buff
Exhaust --> makes you able to kill champions when you are below 25% hp and is also usefull in teamfights

First you start at the bot lane. There you farm until you get 1200 gold for the hextech revolver, or you can also get your gold faster if you get some kills, but DON'T ENGAGE it is too risky, just fight when the enemies engage and are low or if you can't escape anyway. After you get your Hextech Revolver you change lanes with your teammate who is at the top lane at the moment. Then you better ward the dragon to make sure that you will never miss you cleaver and to have some mapcontrol. The following stages of the game are very simple: Win teamfights (this isn't that hard if you don't have a noob team, trust me you normally win almost every teamfight, even if the enemies ignite you, then you better just run away for 2-4 seconds)

Also a very important thing is that because of the high costs of the items you will purchase it is very important to farm and get kills, so you better jungle (healing yourself up on the dragon afterwards) and never camp too long in bushes)
Now the detailed explanation how to heal up yourself using the dragon:
You stay in the middle of your lane, and just throw your cleaver at him. tip: better ward the dragon becasue you will be then always sure that you'll hit him

Pros:
-OP damage
-Infinite and fast healing
-Still tanky
-Very fast

Contras:
-High item costs
-Can't stay inside the enemy nexus for more than 2 seconds

Push your lane, unless you get ganked too often
Jungle sometimes
If you get low heal yourself up using the dragon

If you have someone in your team who is more tanky than you then let him engage, don't engage by yourself. If you are the most tanky one then don't engage in fair 3v3 fights where both teams have the same amount of hp and all spells ready, try to trap the enemies because once they fall for your trap they cant escape from you, not even with ghost