Now, I have used Morde for a long time, trying out new builds, going health armor (off tank) and just pure ap, which i don't believe should be the way to build morde. Morde is a champ that deals tons of aoe damage, and single handedly able to tank 2 or 3 champs at once with his passive. The Rylais is for susatin and slows, being able to slow your oppenents with our E can save you or your team many kills. The Hextech is mostly for the spell vamo from its passive while giving you a nice life steal bonus for your Mace of Spades (Q). The Hourglass is for armor and AP and a super active that prevents you from getting killed if caught... I LOVE SPIRIT VISAGE, it's a mordekaiser item. health, coold down reduction, magic ressistance, and increases all healings on yourself by 20%. If you're still not convinced maybe this will, in team fights, the health is obviously good, the cdr makes you odo more damage per second, the magic ressistance is for that AP carry or AP champs that are tryin to focus you, and its passive makes every ability (including your seal runes) give you health as you deal damage, PLUS the super passive that morde has, which createsa temporary shield based on the damage you do. so, the Adc is focusing you, you ult, E and Q a few times... and I guarantee you that you'll see their health just drop by the second while yours barely moves, and if you do kill people with your ult, the follower's damage heals you for the 20%... HOW OP IS THAT!!!!!

Well, your main damage output early game is your E so you max that out first, following your q but you want to get that w early for suurvival reasons. Ok let's say your pushing their tower with your abilities when you see that you're about to get ganked... you use your ability on the jungler to activate your passive, then you shield yourself with W to gain armor. IF you are level 6, then use your ult to steal some life. You can easily survive and get safely back to your turret, or if your jungler is close, then you might as well try to kill one with your ult and combos which are E,Q,W(on yourseld or your jungler),E, ignite, then ult... your will either get a kill or you scared them away for you to survive

Now I recommend using ignite, flash.. ignite to use with your ult, and flash for runaways, or to catch your enemy... Some other spells you could use are teleport, and exhaust. All the other spells aren't the best with morde, for example, ghost yeah it could work, but flash is faster and you can flash over walls. Heal, signifies that you lose health, which your seals cover that, clarity, he doesn't use mana -_-, smite, morde can't jungle, and clairvoyance is for your support to have,,

Pros cons
-Amazing passive -health dependant without health regen runes
-easy to farm after level 4 -easy to gank because he has no natural escape
-he's made of metal -farm dependant, if you can't farm properly
-crazy burst damage -can be easily countered by range or cc
-very hard to kill if fed -no natural cc
-this build works even if you went 0-10 in lane
-doens't use mana
-clears wave minons like if it's his job

Ok so, farming.. what the game is about. If you can't get 100 cs by at least 15 min, you better off using another champ because morde can easily get 100 cs by 11 min.

Here's how you do it:
after you get level 4, you clear the wave as fast as your can (make sure you ward) then you take your wraiths. keep repeating and you'll be happy with the farm you obtain by 11 min.

Now there are some occasions that you won't be able to do this, for example: your jungler is behind, your facing an ahri/anivia, or they have their jungle warded and can eaily kill you.

This strategy takes practice it will not come around the first game so don;t get mad.
My best farming is when i had 200 cs by 25 min, I was 0-0 but i had a full build at 25 min. you can literally step all over the enemy team without you getting a scrath.