Build 1 (Poke-N-Dive): Keep Inner Beast up whenever you engage enemies, throw out your Cocktail, and only dive as a Worgen to secure kills.

Build 2 (Heavy Melee): Much harder to pull off, and I feel the more range focused build is much better for Greymane's overall play style. This build has a lot of burst if you manage to stack Wizened Duelist, but suffers since you'll be diving in more to DPS and as a result being focused down.

General Tips:
-Poke, poke, and poke some more. Stay at range and land Gilnean Cocktail whenever it's up on the enemy team/creeps. At level 16 always try to throw Gilnean Cocktail with Inner Beast active for the bonus damage.

-Greymane has no self-sustain. Be overly cautious about your positioning even at range. When diving to secure a kill with Darkflight remember you will have to wait for 5 seconds before you can disengage.

-Worgen form does a ton of damage and is useful for lane clearing.

-Go for the Throat can sway team fights in an instant if you land a killing blow and the second free cast. As with Darkflight, be careful of where you'll be landing. You can be a bit more brave if you have a support on your team (not always the case with Quick Match, as we all know...).

Finally, have fun! :)

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