Personally I’ve got 21 in offensive, 6 in defensive and 3 in utility.
If you want to make a mega tank, put the majority in defensive masteries and the rest in utility, but that would defeat the purpose of an offensive tank.
Woah Woah Woah! If your going to do masteries its best to split it 21 main 9 sub. The 3rd tier in all trees (minus utility really) its better to invest towards rather then split it off between all 3. The low tier goods just dont give enough umph unless its like Exhaust or Teleport benefits. Other talents in each just aren't that benefitial.
If focusing pure tank by far 9/21/0 is the BEST tank build. Investing on utility, specially with Mord, is just a complete waste. 9 In offensive gives CDR which is invaluable to him and the 15% Magic Penetration for a tank that thrives off earning more shield with Abilities is incredibly useful. It makes him much more of a tank then 0/21/9.
The majority of my runes are armor penetration. All my Mark and Quint runes are armor penetration which comes to +29.
My glyphs are magic resist which comes to +13 magic resist.
My seals are armor runes and come to +13 armor.
One of the benefiting factors of Mordekaiser is his shield. That greatly help your defense.
Again... wtf? I can take it if you build offensively with him, but overall Mord takes benefit from Magic Penetration. Armor Pen doesn't do anything for him. With Mord if hes going to be a 'tank' at all he should have dodge runes ideally or health, with dodge in his case proviidng most benefit. With higher Armor and MR he will have with item build, having such small additions of MR and Armor just don't hold benefit.
Red: Magic Pen
Blue: CDR (The less CD, the more he can spam his shield back on)
Quint: Depends. HP per Level is incredibly powerful quints. Dodge can work here or even possibly Magic Pen.
Ignite – Hands down this is the spell to have with Mordekaiser. This in combination with his ultimate can deal killing blows and give you an extra champ to work with.
Flash – Great for getting out of hot spots when needed or to catch the last enemy with your ultimate and ignite combo.
Really the important spell to have is Ignite, any other is your personal preference and playing style. I only suggested Flash because it can be used offensively and defensively depending on the situation.
I have to disagree with Ignite. It can be useful, but really I don't find it to be 'hands down' best spell for him. Chances are if your popping to finish someone off, you should already have them. Ignite later on just doesn't give to much benefit to really be worth wild later. Again its by far not the worst but I wouldn't call it the best.
Flash I do agree with being valuable. Flash can catch up to people in which he can provide another quick Siph can finish off a running champion. Flash also allows him to run out should the tides be turning and escaping the middle of a fight should he be pushed into it. Either flash or cleanse can help a lot.
If your going offensive, I highly recomend getting Rally. In team fights rally can keep mords health raising and boosting team damage. The boosted AP will increase his damage to some degree (though unfortionately his low AP rations won't give to much benefit) and most of all it helps the entire team.
Exhaust is another great spell in order to reduce damage from a carry and to allow more hits in with both his abilities should someone try to run. Teleport works great for him to quickly move and farm and stop tower pushes. Summoner spell though it varies depending on taste.
Why wait to upgrade Mace of Spades till lvl 11?
The damage dealt is related to your base damage. The trade off of not upgrading either Creeping Death or Siphon of Destruction isn’t justified by upgrading Mace of Spades. It’s better to use it in later levels when your base damage is actually high enough to do damage to champs.
Countless times I’ve been able to go up against other Mordekaisers that I’m able to out damage and out shield and they end up running away simply because of their skill choices.
I have to disagree. I think mace of spades is worth some investment in over shield. Its another source of generating more shield and can help out with farming. Otherwise I do agree in leveling it last.
Ninja Tabi (if other team has more dps)
Mercury’s Treads (if other team has more casters)
Berserker’s Greaves (if other team is more tank heavy)
Warmog’s Armor (built from giants belt)
Thornmail or Sunfire Cape for final item (Sell Doran’s Shield)
You can switch out one of the Sunfire Capes with a Force of Nature or Banshee’s Veil if the other team is relying heavily on their casters.
In several instances I’ve been able to get above 5000 HP, 200 armor and 125 magic resist and able to tank all 5 champs focus firing on me and come out alive with a decent amount of health. This isn’t mentioning the added shield which adds about 800 more HP at full capacity.
I disagree with your item build. Seeing as you want a "Offensive Tank" I notice you lacking what makes him do such. CDR is a big part in keeping his shield up and doing damage. Frozen heart gives both the CDR, Armor, and attack speed debuff giving him more tank power and providing more damage.
Warmonger's is a bad item on Mord. His shield allows him to take hits and keeps his health topped. With Warmonger's your just buffing the HP that should never be teached and lowering the damage his shield can take. Force of Nature by far plays a much more effective weapon giving more Health regeneration and a chunk of MR lowering damage recieved. When his shield is up his health will be healing up much more.
If your going to get any offensive boots, by far the best boots to get are Sorcerer shoes. The Magic Penetration is invaluable in increasing damage output and thus giving his shield more bang for the buck as abilities do damage. Beserking are just not valuable on him at all.
Other items you have I won't talk against since it is your own build. It works for you and all so as far as that goes I'll leave it open. Its by far not my item choice but none the less i don't want to completely bash your guide