olaf E makes true DMG That is nice ability againts tanks and also have low he gains attack speed when he losing HP what is also nice and makes him stronger.His ulty makes him really op he can move through all players and make nice focus. He can't be stuned/slowed/feared... and he also gains Armor and Magic resist. his Q makes nice dmg and good poke if in early game when you pick it your cd will be reduced for 4.5 CD so when you can to take it you can use it again . When we speak about nocturne. His Q is nice for focus and chase. He can see where invisible targets move if he hit them with Q also make nice dmg. his W sheild him from one ability and gives him passive attack speed. His passive makes dmg every tagets around that one he attacked. And that makes him better in jungle.His ulty is also good for ganks and fear So olaf is more better on top and nocturne in jungle.