hi,
mordekaiser is the way to win ranked, he can dominate almost any champ and makes the enemie champ only able to farm under hes tower ( you need mucho wards cuz you will mainly be standing in the enemies half (not to far, after each wave stand in the brushes), i run ignite for ulti so the support cant heal up the carry during my ulti and flash is best to get away from ganks in laning phase and also to get away in team fights or get that last E to kill a champion

ITEMS
you start with regrowth obiously becouse you will reg all you life very fast and you will use it to make force of nature anyway (althou if the enemie team only haz 1 ap carry and he not doing so well i might sell reggowth for needlesly large rod and keep the 48mres cape for a while) you need to farm atleast untill you can buy boots and hexteck revolver +3-6wards depending on how long you wanna stay in lane you wont be forced out of your lane with hp reg and spell vamp unless they gank with jungler and mid than just call for help to hold lane. after that you just buy accordingly to who you are facing is he dps? buy armor first mres? go for force or just a cape if hes the only one(unlikely since hes top and they prob have ap carry mid too) are you dominating anyway? go for rylaiz I still get the life first thou, so it will be harder to get ganked and die. if you jsut keep dominating after rylays i just buy chain vest and mres cape than rabadons or if they have lots of autoatackers go for thornmail early if they dont and you get fed get frozen heart its insane with the cd and atackspeed reduce aura (just a bit more expensive so thornmail is usually the way to go since it also scales so well with your passive not taking dmg but stil returning it) at last you upgrade your revolver to a gunblade but this hardly happends. ( if a team consist of 3 phis dmg orriented champions (or 2 rly fed ones) you could switch rylays for sunfire cape)

so end gear would be mpen boots(if they are very cc heavy ofc get mercs)-rylays-FON- thornmail or frozen heart-rabadons/gunblade
if your team isnt doing so well and rly needs you to tank you can switch rabadons for warmogs but ive never had to do that since i dont think life scales so well with your passive and there are so many champions with dmg based on max life these days.

TEAM FIGHT
with this gear you can usually kill there ranged carry with your e/ulti/ignite and a litle dmg from a team m8 but watch out if he buy QSS than you must use your ulti to kill him so make sure you last hit him with it or when you are sure he wont be fast enough to cleanse your ulti befor dieing, once you get there ranged carry its easy street to quandra or penta just make sure to keep your pet walking to enemies if hes not shooting and its usually nice to give your W the the person who is getting focused even if its a tank if there are 2-3 champions on him your W will make nice dmg and keep your shield up to soak up dmg.

RUNES
well they should be standard you could switch armor en mres for p/lvl ones but you rly want to dominate and once you do you rly dont need that extra armor/mres on lvl11+orso
i also like to pick up one mpen quint cuz I like 10mpen :P quints are jsut personal preference you could run anything from life to armor/mres/movespeed/hp reg even ap but i dont recomment it it will only improve your early game dmg by a litle bit.

MASTERIES
well 21 utility is just nsane they will almost never be able to gank you with your flash on semi low cd the 9% cd is ncie aswell and def tree althou nice is just rly not needed and i know the utility tree also gives allot of **** wich morde doesnt need but you rly want the 15% mpen from off tree and the exp from utility so than you would only be able to go 2-3 points in veteran scare(life) wich is the only nice one besides flat armor/mres
and the cd in utility tree is just so nice in end game when i am fed and bought a froze heart you have litle under 4sec cd on your E with insane dmg.

LANING phase
oke so your not the killer champion on lvl1 so statr by being a bit def and just last hit with auto atacks and harass a bit with your E onc you get lvl3 with lvl2 E and lvl1 W you can just put W on yourself stand in all 6 minions and last hit with your auto atacks and keep harrassing with your E once you get lvl4 you can use your q for farming aswell unless you fight a melee champion than once get gets close give him Q E and keep farming, you should be able to farm just as fast as the ad carry bot since you will only need to recall once or twice, usually there be an off tank top (usually phis dmg type too) if you play vs one of these you should even harass him under tower to deny him last hits ( you must have wards by now) becouse these champions alrdy buy gold per sec items (2x usually) they will become insanely strong late game if they have proper last hits aswell make sure to keep them low with your e so they wont even think about last hitting you can even give your minions W to make sure the tower gets the last hit but carefull with this cuz W's cd is very long and you need it to keep up your shield withoud using other skills ( to keep them for either last hitting or harassing)

so this is my first guide its probebly very boring and looks ****py but if you want to raise your elo mordekaiser is the way to dominate top and thus have great influence on mid/late game and when you succesfully ghosted the enemie carry its almost a won team fight
so comments on what you think and dont flame like a kid who needs attention cuz i will just ignore it( and I alrdy know the guide haz prob allot of grammar mistakes but i bet everyone can understand the content so dont flame about that either)