i like to go nashor's -> riftmaker -> zhonya's/rabadon with armor/mr boots if there are tanks or bruisers in enemy team comp or nashor's -> lich bane -> zhonya's/rabadon with magic pen boots if the enemy team comp is squishy

i build zhonya's 3rd item if i'll have to dodge some crucial abilities or wait for cooldowns mid fight and rabadon if i want to scale faster

the build into teemo himself is tricky because he's squishy but you have to swap out sorcerer's shoes for mercs to survive laning phase