Well i didnt really have time to explain much but this is how i play rumble. I build him tanky enough so he can last in the fights and then once sunfire and FoN are built get some damage and you are unstoppable. If you feel like the added defenses are not neccessary switch out FoN and sunfire for abssyal and zhonyas and you should be fine as well but personally i like the speed boost from FoN and the area of effect from sunfire. Although i havnt used him much yet the game i have done i went 8/2/8 and 3/1/4 ending the games rather quickly by getting first blood in each. To get first blood easily just sit in the bushes and spam flamethrower until your heat is up the cd is low enough without cd reduction to do this.