During the most recent winter solstice - when no other night during the year is longer - a being like no other emerged from the forgotten alleyways of Noxus. Standing eight feet tall, and concealed within a razor-sharp armored shell, he came to be known only as Mordekaiser. The nature of what lies beneath his metallic carapace is a popular subject of speculation. Many allege that he is a mortal man with a heart that has hardened to iron. Others insist that he is a dark specimen of the undead. But there are some who whisper warnings that he is merely a foreshadowing of something terrible and unprecedented yet to come. Despite the public conjecture and curiosity, none have discovered what lies beneath his alloyed exterior. What is known is this: Mordekaiser arrived unannounced at the Institute one day and, with a rasp that crept ice up the spines of all within earshot, requested to join the League of Legends.

Upon glimpsing his fearful visage, most keep their distance, fortunately unaware that his touch bears a sinister scourge. Those who stumble within his grasp fall victim to incurable maladies. In fact, Mordekaiser seems mystically attuned to sickness, as if it feeds and comprises part of his chilling essence. He now stalks the slums of Noxus, drawn to the plague-ridden and diseased. However, there is something in his clever tactics, something in his noble stance, and something in the tone of his unearthly commands that has led many to believe that Mordekaiser is more than just a foot soldier. Some see the distinguishing characteristics of a general. While many have learned to accept the evidence of this unsettling possibility, a lingering questions keeps them wary at the witching hour: if Mordekaiser is a general, what nightmarish legion lurks at his command?

''The common perception is that the encompassing armor protects him, I fear that - for the fragile time being - it actually protects us.'' - Rozuel Fecirem, Arch Adjudicator, noted in Mordekaiser's eligibility evaluation

When Mordekaiser's health falls below the cost necessary to use a skill, his health will drain to 1 HP. Any subsequent spell casts will bring him down to 1 HP, meaning that he cannot kill himself through his own abilities.
It is often a good idea to farm conservatively early game, as your Iron Man shield is not nearly as effective as it is late game.
Mordekaiser's best defense is maintaining his Iron Man shield by using his abilities. However, keep in mind that spamming skills will result in low health without enough health regeneration/spell vamp.
Iron Man is a great late game ability allowing you to survive during team fights longer than most other champions, as long as you use your abilities constantly.
The damage from a level 2 Creeping Death is a bit greater than the damage from Sunfire Cape but Sunfire Cape still gives more armor than level 5 Creeping Death . This makes it very effective at farming minions, and during fights. The bonus armor that it gives can also help tanking turrets. You can use it on an ally while staying in the back of the fight at low health to build up your shield and get assists.
Leveling up Siphon of Destruction first gives you the ability to poke at a range, but mind its health cost, as it can quickly bring you down below a comfortable amount.
Siphon of Destruction will not damage enemies behind terrain walls, even if the walls are thin enough. Also, it will not damage enemies on the opposite side of a tower.
Creeping Death is usually the best ability to gain shield health, due to its consistent AoE damage.
If you use Children of the Grave on their attack damage carry and take down the champion quickly, the ghost's auto attacks will fill your shield up and help you stay alive longer.
The combination of Ignite and Children of the Grave is deadly to almost any wounded enemy.
Like most other secondary units, the soul you've stolen with Children of the Grave can be controlled using Alt + Right Click. However, unlike most secondary units, your ghost acts as an allied champion, and will be affected by abilities that can only target champions, such as Wish, Requiem, and Infinite Duress.
Children of the Grave can also be used to block Caitlyn's Ace in the Hole, the primary damage/effect of Ashe's Enchanted Crystal Arrow, or Graves's Collateral Damage.
Avoid casting Children of the Grave on champion clones or champions with death-preventing abilities (ex. Guardian Angel).
Try and wait until your target is fairly low health before casting Children of the Grave, as most people will run when they see they have the debuff on them.
If you are using Ignite, keep in mind that its range is much shorter than Children of the Grave, and so you should try to use it first.
Additionally, if you have the mastery Summoner's Wrath, using Ignite first gives a bonus 5 ability power, causing Children of the Grave to do more damage.
Mordekaiser's ghost will attract tower aggro first, but if it attacks a champion while you are in range, you will become the new target. If you cast Creeping Death on the ghost and it hurts an enemy champion, you will draw aggro instead of the ghost.
Mordekaiser is very capable of taking a solo lane against 2 enemy champions, reaching a higher level than both of them while effectively harassing and farming at the same time. If you harass them enough, you can potentially get a double kill with your ultimate.
Take advantage of the fact that many people underestimate Mordekaiser's damage once he gets his ultimate, when combed with Ignite and his other abilities he can kill enemies who feel safe if he can get in range of them

Mordekaiser is best built as an off-tank mage as he greatly benefits from both survivability due to his melee range and shield and ability power because of his relatively high AP scalings.
Getting spell vamp from Will of the Ancients or Hextech Gunblade is very important for Mordekaiser, since it refunds the health cost of your abilities and more, allowing him to recover health.
Also, Hextech Gunblade greatly increases the damage dealt on Mace of Spades, as it scales off of ability power and Bonus attack damage. In addition, the active is a strong CC, as Mordekaiser has no natural CC.
Do not be afraid to build some health items. Armor and magic resistance make your shield more effective, but without the addition a health item or two, Mordekaiser remains rather fragile. Common items include Rylai's Crystal Scepter (to add needed crowd control to his abilities while also increasing his magic damage) and Sunfire Cape (which stacks remarkably well with Creeping Death, in addition to armor it provides).
Getting magic penetration runes, and Sorcerer's Shoes allows you to harass better, get more kills early in the game, and even late game against those champions who do not have any magic resist above 30. The full power of your ultimate can be extremely devastating to squishies.
Building magic penetration makes your abilities hit much harder, giving you even more shield and letting you stay in the fight for longer without sacrificing damage. It is often more effective than stacking health in most situations.
Magic penetration usually is more effective on Mordekaiser than flat ability power, as his ability power ratios on his abilities are relatively low.
While low level you can counter Mordekaiser 's Children of the Grave with health potion.
Comit to taking Mordekaiser down. Iron Man can easily drain away, but will block quick pokes. Crowd control effects such as a silence or stun will also prevent him from growing his shield back for a short time.

MACE OF SPADES :
(Active): On next hit, Mordekaiser swings his mace with such force that it echoes out, striking up to 3 additional nearby targets, dealing magic damage. If the target is alone, the ability deals 65% more damage.
Additional target radius: 600
Cost: 25 / 32 / 39 / 46 / 53 health
Cooldown: 8 / 7 / 6 / 5 / 4 seconds

Magic Damage: 80 / 110 / 140 / 170 / 200 (+1.0 per bonus attack damage) (+0.4 per ability power)

Single Target Magic Damage: 132 / 181.5 / 231 / 280.5 / 330 (+1.65 per bonus attack damage) (+0.66 per ability power)



CREEPING DEATH :

(Active): Unleashes a protective cloud of metal shards to surround an ally or himself, increasing their armor and magic resistance and dealing magic damage per second to enemies in the cloud for 6 seconds.
Range: 750
Cloud radius: 250
Cost: 26 / 32 / 38 / 44 / 50 health
Cooldown: 20 / 18 / 16 / 14 / 12 seconds

Armor & Magic Resist Bonus: 10 / 15 / 20 / 25 / 30

Magic Damage Per Second: 24 / 38 / 52 / 66 / 80 (+0.2 per ability power)

Maximum Magic Damage To A Single Target: 144 / 228 / 312 / 396 / 480 (+1.2 per ability power)

Siphon of Destruction :

(Active): Mordekaiser damages all enemies in a cone in front of him, dealing magic damage.
Cooldown: 6 seconds
Range: 700
Cost: 24 / 36 / 48 / 60 / 72 health
Magic Damage: 70 / 115 / 160 / 205 / 250 (+0.6 per ability power)

Children of the Grave ( ULTIMATE) :

(Active): Mordekaiser deals magic damage to the target and curses it for 10 seconds with a damage-over-time effect. The damage is equal to a percentage of the target's maximum health. Mordekaiser heals himself for the damage done.
In addition, if the target dies while under the effect of the curse, their soul is enslaved and will follow Mordekaiser for 30 seconds. During this time, Mordekaiser gains 20% of their ability power and attack damage. The spirit in turn gains 75% of Mordekaiser's adjusted damage, ability power, and health totals.
No cost
Range: 850
Leash range 1125 (estimate)

Cooldown: 120 / 105 / 90 seconds
Initial Magic Damage: 12 / 14.5 / 17% (+0.02 per ability power)

Magic Damage Per Second: 1.2 / 1.45 / 1.7% (+0.002 per ability power)