Most of the ppl thinks that sion=tank, but it's not true... sion is an OP dps.

He almost impassible to kill while you using your ultimate(20 sec), it's usually enough to get double/tripple/quadra kill

With this build u have enough crit strike and attack speed(specially when your ulti is on) but u might need more AD or armor penetration(i prefer AD)

as a first item get Vampiric Scepter, then update it to Executioner's Calling then how it said in a build... u ending up with > than 100% of crit strike, so fell free to sell calling and get frozen mallet or bloodthirster or last whisper depend on enemies

u need Cryptic Gaze first specially if you planning to gank and bring first blood to your team, second spell should be Enrage(once u learned it press "E" and NEVER press it again XD ). Vampiric Scepter will give u enough lifesteal so u wont be wasting your HP on Enrage, and this spell gives you good amount of AD for early game that's why u wont need any AD items untill u will get second phantom.

You should do enough dmg so enemies will run as soon as the saw you, that's why u would need ghost and exhaust, so you can catch them ->> stun ->> kill easily