Mundo does some AP damage and so i figured with all his poke and massive move speed at 6 with alot of spell pen he could tear through somebody. Yeah he can do that. But dear random person you might ask. Wtf? Stick with me for a second here ok?

The core build is pretty simple. SPELL PEN. Well actually its not THAT simple but still not very complex. First back if you have been farming well hextech revolver and boots is your best choice. Counter your hp loss with spell vamp. Go into your haunting guise or spell pen boots and then hit up will of the ancients. This will make your cleavers give you more hp then the cost so your poke also becomes a really good form of sustain and cc. This is why you max it first then your W even though the W is the main source of damage. Then build that haunting guise into Liandrys Torment in order to make your W burn the enemy's even more and in combo with cleaver your unstoppable (Kinda). Ok after that build a spirit visage or sunfire cape but visage is more core and then a Warmogs. This will make your regen just as insanely awesome as tank mundo. Then as your final item pick up anything pretty much. Rylais, Void staff, and guardian angel are some of my more frequent pick ups.

The Pros
1: Very high poke vs melee opponents such as zed or talon and he doesn't burst easily
2: Good ability to farm even when against poke heavy champs such as Xerath.
3: Mundo goes where he pleases

The cons
1: You have to be right on top of your enemy to do damage so your sort of a extreme close range glass cannon which is terrible
2: You are a melee mid without the constant threat of burst that makes other melee mids viable such as of course Zed
3: The biggest Con is very obviously that you can just play him in the jungle or top with more success. But that's no fun.

We roll with 9-21-0 to get as much resistances and hp regen to try and negate poke and be able to farm up our precious core item build. Make sure to grab Perseverance, the maximum hp percent and the flat hp add.

Trying to scale into late game with the armor and magic resist scaling runes is what i find the best choice. Make sure to have AP quints however because we are AP Mundo after all. And of course in order to spam cleavers like none other cdr runes is just perfect. Oh and also Hp regen, Because ya know welcome to Mundo land.

If you can afford to put a point into your E at early levels to make last hitting really easy and quick so you don't get harassed too much. If not max out cleavers and farm as best you can with them without getting murdered. Oh and i mean E when your not getting poked q when getting poked. Im putting a very heavy emphasis on farming up your core before mid game because mid game is your strongest point with this build.

Max out cleavers for the poke and sustain with spell vamp, Then your W for more damage and of course take ult when you can. Max your E last but make sure to have at least one point in it for last hitting.

Your main goal in a fight is to try and make as many people swallow your W as possible. If you can get on a tanky champion Liandry burn and all your spell pen will eat them up so make sure to choose your targets wisely. Use your ghost to engage or close the gap in order to save ult for the middle of fight to negate damage.