Early Game Buy left to right. If you lower the Bullet Resistance of the enemy, it means you'll deal more Melee Damage to them! If you feel like you'll parry a lot, get Rebuttal in the Parrying section! Upon acquiring Express Shot, use your Alt-Fire (RMB) to deal big damage! Just remember to wait 4s between shots to get its effect! Use it after a Heavy Melee!
Lane Healing Buy one of those items to remain in lane and not miss out on souls! Sell the item you picked later. Mystic Regen can be triggered by Puddle Punch (3) thanks to Spirit Strike. Extra Regen is the most passive option.
Mid Game Buy left to right. Enduring Speed is optional but should be bought if the enemy has a lot of slows or tends to escape you. If you are able to time parries well, grab Counterspell as it'll make you able to parry many ultimate abilities!