Not Updated For Current Season
Sorry for my bad English.
I prefer this build for Pantheon, as it works really good to me.
1) As you see you have not lifesteal, but you have 50% critical chance, that means that every 2nd attack you will make about 1000 damage to your opponents. So with 5-10 strikes they are dead.
2) I prefer this skill sequence as the aegis of Zeonia at level 3 is usefull to stun and obviate an enemy to kll him.
3) When you have Doran's Blade, Sword of the Occult, Brsker's Graves, Yoummuu's Ghostable, Last Whisper and Infinity Edge, you should sell the Doran's Blade as you don't need this now, and buy The Black Cleaver for more Damage
4) Now you are realy unstoppable. So you should buy and the three elixirs, as these will be activated auto. Every time you are doing recall you should buy these.
5) I suggest you choose Clairvoyance as you could attack with skyfall to someone who is runnig back in a safe place for recall. Also you can see if any oppoents want through you in a trap.
I suggest you Ghost for escaping when you have less HP, and for quick supporting to the attack of your team
I tested this build first time when i see a video with a really g-g-godlike Pantheon with 41 kills! I tested this, and it works.
Thanks for reading.
Sorry for bad English