I've been playing Pantheon since I started playing League of Legends as he was on rotation the 1st week I started playing. So I've been playing him before the nerf and after his recent buff/nerf (I think buff).

This build is designed for those who want to get kills, and lots of them. Whilst still being able to stay alive late game. In order to do this the occult is essential.

These runes are the best possible runes for pantheon.

Armour Penetration Marks are obvious allowing early game dominance and steady damage late game.

Armour Seals are also kinda obvious, as in the lane the majority of opponents are AD, however if they are AP, their damage is minimal early game apart from maybe one ability that they can only use once due to cooldowns.

Crit Damage Glyphs are I think the best on pantheon due to his passive which allows him to crit if the opponent is under 15% health. Increasing this critical damage means that the ability to finish someone off is much easier, especially since now his spear has this passive.

Attack Damage Quints mean you'll be doing huge amounts of damage early game with your spear allowing you to harass for a short while until you reach level 3 where you jump on your opponent, heartseeker strike them and finish them off with a few auto attacks if possible and a spear.

Always keep your mana under control as Pantheon as you can eat it up very quickly, mana regen runes are an option but not essential if you're patient with your abilities.

Pretty obvious AD Carry masteries 12/0/9. I go with the 9 in utility for the mana regen and the experience buff allowing for me to increase my heartseeeker strike as early as possible.

Get the occult as early as possible so you can start stacking. Having an occult makes you more aggressive as you know you're trying to stack, whilst also stopping you from doing anything stupid because you could lose them all!

Phage allows for you to jump an opponent and with exhaust and the slow from the phage, pretty much prevent them from escaping.

Vampiric Scepter is great to get next so that you don't have to recall due to your health as you can regenerate off of minions. It also allows you to go for buffs easily.

Frozen Mallet is just a bigger phage, so you know, more slow, more health, more damage.

Atmas next to get more AD from the health gained from the frozen mallet whilst also giving crit chance and armor.

Go for the banshees next if your having trouble with AP champs because until now you wont have much MR. The added health from the banshees also increases the use of the Atmas.

Finally finish off with a bloodthirster for ad and lifesteal to increase your chances against other dps champs in a one on one situation.

Early on, spear is essential in case the opponent in your lane is ranged or you like to harass. Most people next go for his leap, i prefer to go for the heartseeker in case someone say exhausts you and you must turn and fight, the damage early on is great. After this it is basically get the leap, them max heartseeker first followed by spear followed by jump.

Exhaust is pretty much essential on all dps champs I feel especially with the mastery point reducing armor and magic resistance.

Flash is better than ghost for pantheon as it allows him better escaping. It also provides better attacking as you essentially have two flashes with your jump when chasing. The frozen mallet means that there is no need for ghost in chasing. Another use for ghost is to get back to your lane, however Pantheons ultimate means getting back to lanes is easy.

Pros:
Tanky
High damage if stacks are going well
Dominant early game due to runes

Cons:
Somewhat dependent on the occult however if the stacks arent going well, get an infinity edge or Yommu's etc...
Low MR early and mid game, but as always you can make this build suitable i.e. get MR early on.

This is my first write up of a build but I have lots of experience in playing pantheon and I can tell you that this is a tried and tested formula. Ive recently been playing other newer champs so I would only be able to insert one picture from my match history but it would read 11/1/10 !!!

I welcome any feedback but as with all guides, its a 'guide' not a rule book.