magic pen because it's an ap build
atk speed because it will make mace of spades useful
armor to make you more resistant
cd reduction to have your spell faster

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to have a good def and more hp regen and mana regen

teleport to be everywhere
fortify to deal more dmg to minions to have more armor

always chose the ad dps
the best choice
tryndamere ( hes hard to get but he kill easily his teamates)
master yi
etc.
or at least try to get the tank or anivia (she have her passive)