Hi everybody,
This build is to create an extremely hard to kill mordekaiser :) I use this build myself everytime and it always works like a charm Especially from the moment you get the second armor :) now NOTE that this item setup can be altered depending on the enemy team :) for example if you get a full magic damage team against you just replace the thornmail with abyssal scepter. and continue the build so on ending with a Spirit Visage :) BUT note that even if you opponent team is complete physical damage still get Force of nature just because of the health regen and speed increase.

In my opinion Mordekaiser is just a tanky tank that is a potential spiked wall of doom. So naturally I made his mastery build a tank build with some damage. :) the magic penetration because mordekaiser is almost 100% magic damage so might as well boost it up :)

spells are pretty straight forward :) just sprint and ignite all the way :) sprint can be changed to preferences :) but ignite is a must cuz that can give you so much damage from level 6 on out together with your ultimate ;)

As you might be aware of Mordekaiser is very good in keeping a lane up by himself :) just try to keep your shield up with the E and Q attack so that you become less likely to die in a gank or can even be able to tower dive. :)
at level 18 teamfights make sure you activate your W attack just before entering combat to suck up a bit of damage from the burst attacks of your opponents :)