Play rumble (or rammus) top and go full tank,
Rammus+Ga+thorn mail = dead enemies
Other items I get: mogs/mercs/sun fire/
Spirit or dead mans (depending on if enemy is heavy ap or ad)
Use the keystone mastery that heals you for 40% of your max hp every 4 seconds; on hit effect when basic attacking champions.
You'll do a bit bad/neutral early on, but once you get ga and thornmail you start getting fed easily and end up becoming unstoppable
With rammus: you force the enemy squish to attack you and watch as your W+thornmail combo ends them, make sure to Q first and ugly for AOE dmg
For rumbs: Ult, then W>Q />e only if they run away) continue spamming abilities to be overheated to commence the smackdown then just use W to run if needed