It's best to play very passive early game, and start to begin your aggression mid game if you are on track or ahead with your build. Mid game is where you should get a lot of your kills that start making the enemy team worry. If the game drags out into late game, you'll need to start farming and pushing out lanes if they are pushed too close to your base. The gold from this will help you easily afford your elixir late game. Your ult starts to gain it's damage after you build Black Cleaver, so don't get too cocky with it early game.

I'll be adding to this guide pretty often if I discover an error or see that I can add to it or make improvements. Se be sure to check it out once a week to see what's new!

Goodluck out there, hope to see you on the Rift!