This guide mainly focuses on the items. I believe there are good guides out there already about playing Mordekaiser. I just wanted to share the build that i have been very successful with.

To start with, this build is heavily inspired by "MyDadDied"'s mordekaiser guide. Four of the items are the same, however i believe the two items I've changed, and the purchase order, are a significant enough change to warrant a separate build.

You want to kill people don't you? Well unfortunately they don't like dying, so they buy magic resist. This helps negate that.


For those annoying Tryndameres.


For those annoying Veigars.


Having a large flat health bonus works wonders early game! Three of these gives you 78 bonus HP from level 1. Nothing to write home about but it can make the difference between first blood and "ZOMG NOOB MORD HE'S ALREADY FEEDING".

While masteries are largely personal preference, there are some critical ones picked up in this 9/0/21 selection. Namely, the magic penetration, experience gains, movement speed, and cool-down reduction. All of these are very important for this style of playing Mordekaiser.

NOTE: After you finish your boots, look at the other team and ***es which resist item to get first. If they have an AP carry that is wrecking shop, start with the negatron cloak. Use common sense too, if they have a 100% physical team, you don't HAVE to buy Force of Nature. Buy some thornmail! This build is assuming that the other team is at least somewhat balanced. Although, even if they're 100% magic damage, it can be smart to still get some armor for tanking turrets! /NOTE

All of these items work together to accomplish several goals.

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1) A reasonable amount of resists.
This is crucial to making your shield effective, when you have high resists and you're spamming abilities, it makes it difficult for the other team to even reach your health pool.

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2) A high amount of health regeneration.
Early game this is important so that you can harass and farm with your abilities without losing all of your health. Mid to late game this helps you to sustain a push instead of recalling just for HP.


3) At least one form of crowd control.
Mordekaiser doesn't have any crowd control from his abilities, Randuins Omen (combined with ghost) allows you to chase down that squishy that's running from the battle and slow him for your team.

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4) A significant health pool.
You may think, why would i need a lot of health when i generate so much shield? Shouldn't i just stack resists? In theory that would work, but in practice, if you're stunned/silenced/etc by the other team and can't use your abilities you won't be generating any shield (with the exception of creeping death). This allows the other team to focus you down before you get to have your shot at them. Warmog's and Randuins help prevent this by giving you a large enough health pool (combined with your resists) to survive that assault and come out swinging.

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5) A LARGE amount of AP.
The soulstealer and Rabadons combine to give you a respectable amount of AP. At least 435 at full stacks, and probably more, depending on elixirs and runes. This is crucial. In my opinion, if you don't have a significant amount of AP, you're worthless as Mordekaiser. Your only form of CC (with this build at least) is randuins, so if you're not hitting the other team hard, they don't have any reason to focus you (and on the other hand if they focus your other teammates they will regret it, since you will kill them all :D).
A key point here is that if you're reckless early and mid game you won't get many stacks on your soulstealer. You need to focus on getting as many kills and assists as you can without dying. Luckily, your tankyness will help you survive in many situations where a squishy would have died and lost their soulstealer stacks.
If you're very new to league of legends, i would recommend getting instead of soulstealer. It's really not optimal, but you have to be honest with yourself and if you don't have the skill to keep the stacks on your soulstealer it will just be a waste of money. It is a nice substitute however with a slow for more CC and some more HP!


6) Magic penetration.
Nothing like making your abilities ignore what the other team spent money on :)

The skill sequence is pretty straight forward, your priorities are as follows.


Your ultimate is obviously something you want to take over other skills. I'm not going to go into any depth on how to use this. Just be aware that it not only damages them it HEALS YOU. This can save your life if you're being ganked and have no hope of winning the fight. Just ult the person with the most health (since it's % based) and run like a little girl.


This is your beastly AOE skill. Hits hard and can generate a lot of shield if placed on a minion wave.


Very useful, not only for its resists, but also for generating shield. It can also be cast on minions and other friendly champions. Cast this on that squishy who's about to be hit by Karthus's ult and he just might survive. If you want to annoy melee champions in laning phase, cast this on the tank minion that they're autoattacking, it will shave off a little of their health :)


Not as useful for AP mord, but still puts out respectable damage, especially early game. You should be spamming this in any fight even if it's just for the shield generation.

Ghost and ignite are Mordekaiser's best friends. I will explain why.


There is nothing more frustrating than using your ultimate on someone with very low hp and watching them pop a health potion or heal and survive it. Additionally, one of Mordekaiser's weak points is that an AD champion with enough lifesteal can solo him. This is due to his lack of burst damage. BUT, with ignite, you can pop it on them and watch as they melt while you spam your abilities.


This is critical for catching escaping champions. Flash doesn't work as well for mord because he is more of a sustained damage champion than a burst. There are a few cases where flash would work, but in most ghost does the job better.

Ultimately it's up to personal preference, i could see flash or possibly exhaust being viable as a replacement for ghost. Ignite though is what i consider a core summoner spell for mordekaiser, it's pretty much his best friend.

Pros:
Ridiculous survivability
High AP late game
Amazing health regeneration
An amazing pusher
By late game can carry and tank at the same time


Cons:
Takes skill to maintain soulstealer stacks
Not a lot of AP until late game
Not a lot of CC
Takes a lot of farming (GOOD THING YOU'RE MORDEKAISER)

Obligatory pentakill screenshot with the build. Game was tied for kills and towers, they had a fed vayne so i ult'd her and wrecked shop with the ghost.

Thanks for reading my guide! Please try it and let me know what you think!

I'm open to constructive criticism, if you think a different items choice would improve it LET ME KNOW! I will try out your suggestion and change the guide if i think it fits the goals of this style of Mordekaiser better.