Starting off with doran's shield is probably one of the best items you can start off with morde, for the sole fact that it provides you not only with health, but also health regen which is a key when playing morde. The next two items, sunfire and force of nautre are meant for mid game, and will give u great survivability and help to counter any fed AD or AP players, providing you with armor and magic resist. The next item, rylai's crystal scepter, will provide you with more health again, while giving you more AP to harass, and get those much needed kills at this point in the game. I also like the fact that it gives you a slow, so morde now has some CC, instead of absolutely nothing. Zhonya's hour glass is also a great itme against heavy AD champs because of the fact it provides you with more armor, and also provides you with more AP, which makes morde even more deadly with his abilities. Thornmain I like if your playing teams heavily based upon AD champs, like tryndamere, master yi, or warwick. This almost gurantees you that you protect yourself from these hard hitters.