Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Decent Mord Build for AP/TANK
I use this build and have found it to be relatively successful, especially for more average level players.
Start with a Dorans,s Shield. Buy Sorcerer's shoes. Then, buy a Rylai's Crystal Scepter, then a Warmog's. Then buy Rabadons. Buy Thornmail. Finally, buy a Guardian Angel.