This guide is for a high mobility farming qop. The playstyle is to farm until aghanims sceptre as this is the key powerspike for the hero.
After sceptre we will fight as much as possible and prioritise staying alive and trying to cast as many posion daggers as possible.
You should go for neutral items which either make you tankier to survive longer or reduce spell cooldown.
Also pick the talents suggested for best synergy.

Once you get all the core items the build is pretty much maxed out in terms of dps. You then just need the lvl 20 talent to amp your scream damage and you should try to fight as much as possible, spamming daggers onto the enemy while evading spells with blink/bkb. I like the get a euls/windwalker as an extension item if the game goes long enough. This can be useful after blinking in baiting some spells, creating vision for you team and then being able to buy you some time for blink to come back off cooldown so you can escape.