Renekton is lane bully, he is early mid game champion and if u manage to get nice farm and 1 or 2 kills u should do fine, however nasus is also strong champion but much harder to play. u have to keep farming until u stuck about 400(that should be about min 25 for avarge player) and then u can help others in your team If it comes to late game nasus is stronger
Nasus win late game rene win early game and u can easly gank if u have nasus on top lane because his W OP