So, this build manly structures around a tanky dps build for this champion. Pantheon can produce a high amount of burst damage with a combo; (w) Aegis of Zeonia, followed up by (e) heartseeker strike, a basic attack or two, and finish it off with your (q) spear shot. Recently Pantheon has been buffed, so his ultimate has a lower casting time so it is easier to initiate with, along with almost all of his skills having a lower cooldown, and with a lower amount of strikes in heartseeker strike, but more base damage. Also Spearshot has also acquired the passive that comes with heartseeker strike being; if an opponent or neutral monster or minion has 15% health pantheon always gets a critical hit, So now you can finish people off with a movie like 300 spear to the face, for the win.

Pros:
- very high damage
- Can have good defense
- Works well in any lane
- Can mid against low hp casters (heimer, Veigar, Annie)
- Very good early game
- Hard to kill late game
- Can block basic attacks and turret shots with passive
- Good initiation tool (ultimate)
Cons:
- Not many escape methods
- Not the most effective in team fights
- Not very good against tanks
- Not good against casters that have low cool-down spells
- Not the strongest when alone early game

For runes I like to use the flat damage marks so early game your damage output can be a little bit higher, thats why i synchronized the armor pen quints with flat damage because its highly unlikely to face someone with high armor at level 1. Basically i used those two to increase the chances of my lanes ability to get first blood. I also use flat armor in seals and flat magic resist in glyphs so that i can sustain a tanky-er type build.

These masteries are built so you can spam your spells as often as possible using as much CDR as possible.
Taking the improved ghost and exhaust can help you escape or even finish someone off.
also taking the improved Armor penetration in offense for higher dps, and greed in utility for easier farming and gold increase.

Dorans blade: The health, damage and small percent of life steal can be amazing for your dps early game, you can put out suprising damage

Mercury treads: Since generally you may be the one initiating you want the tenacity to be able to get away if necessary or to get off of a snare or stun or slow etc etc.

Trinity force: All the bonus' that you can get from this item can make you tanky, bursty and even quicker, benefiting you in almost everyway.

Warmog: This will give you a lot more health, and health regen which is absolutely necessary for this tanky dps build

Bloodthirster: Now this will give you the damage and lifesteal to 1v1 most characters, this synchronized with the amount of health you get from warmog can be extremely useful and devastating.

Atma's Impaler: This synchronized with warmogs can give you a large amount of attack damage. and the critical chance with yourr passive can be a devastating combo for this build.

LATE GAME OPTIONS (sell dorans blade..)
Infinity Edge: an amazing finisher, this can drop people quickly, even late game.

Frozen mallet: yes, you already have a slow, from tforce, but the slow from this is every hit, and the health and small amount of damage can be a game changer

Banshee's veil: Only if you are getting dominated by caster, this along with Force of Nature can be necessary.

Thornmail: Once again only necessary if you're getting dominated by high dps characters that rely on auto attack.

MAX OUT HEARTSEEKER STRIKE
- The earlier you max this out, the earlier you can put out some devastating dps in any lane.
Second: Aegis of Zeonia, the stun duration increases helping you lock down and secure people for easier kills.
Third: Spearshot, this should never NEVER EVER be your main source of dps. I see so many bad pantheons play like that and it just upsets me when you can get almost quadruple the damage in one skill and in half the time..

Ghost: SO necessary for getting away, or even tower diving someone, along with your passive it can be extremely useful

Exhaust: This helps if you are in trouble in a 1v1, or even if someone is chasing you, use that on them, lead em to your team, bait them etcetc.

Early Game
Lane as long as you can, getting last hits and trying to get your stun off on any opponent that happens to push farther than they have to, good champions to lane with
- swain
- Nunu
- Teemo
- Ryze, lux, Morgana.
these people can help you get kills early because some can slow, blind, snare. Which can help you get your combo off stun, heartseeker, spear.
Mid-game winning.
After you take one of their turrets, roam around, steal their jungle and try and help other lanes push to and take there other teams towers down.
Mid-game losing.
If they have taken one of your turrets, try as hard as you can to solo a lane, or take one of their turrets, this can change the tide and grant your team some map control.

Late-game Winning.
Take baron and inhibitors as often as possible, punish them for over extending and make sure to keep the pressure on. By this time you make your decision wether to buy either of the late game items i have listed.
Late-game losing.
FARM FARM FARM oh, and defend if you can get fully built along with your other teammates and carry them to victory by all means do so, if you think you can ulti to backdoor turrets, then do it like mentioned above, this can be a game changer.


DONT PLAY AGRESSIVE
believe it or not, you're opponents are smarter than they look, wait until they make their first mistake, and punish them for it.

HOW DO I GET MAX DAMAGE:p
Like i mentioned before, you must abuse you're combo.
W-E-Q
you can even initiate with
R-W-E-Q
this can either kill them or get them low enough so that they'd have to b, and give up a turret.

Rule #1 never ultimate there nexus obelisk, dont be that guy
Rule #2 if you can turret dive a low health enemy safely, without giving up a kill, use your ultimate to do so.
Rule #3 You are pantheon, but you ARE NOT JESUS, do not ulti their whole entire team all by yourself.. unless you have like 6 levels on them. maybe, but you're still pushing it.
Rule #4 Don't kill steal with it, secure kills with it meaning if you can kill someone that a teammate or someone else cannot using the ulti do so, generally you want to put them in a position where they would have to run back towards your team rather than toward there own turret

Read this build fully, try to understand this character and how to play him. learn how to use the skill properly and support your teammates as much as possible, farm, get fed
kill them all, and gg.

Comment and gimme suggestions first guide.