I will occasionally update my Pantheon.
If you have any trouble following my guide, msg me and I can show you how my Pantheon works out.

Ever since Dominion my Pantheon has been destroying (cept when I get random Bugsplats)

Hey guys, its my 2nd build I ever made on Mobafire.

Lots of people tell me my Pantheon is excellent and bunch of my opponents ask for my build. (So I made this!!)
But unfortunetly many other people say Pantheon is useless and is no longer a viable carry ever since his nerf (W was weakened harshly and his E was nerfed in damage) but I can strongly disprove that statement with this build.
I can carry, middle lane (against morde/vlad/shaco/etc) and win (if my team doesn't screw up)
And I can smash and dash with this all powerful champion.

Doubt Pantheon's viablity? Play a round with me on my team or against me and watch my Pantheon storm the enemy. Or at least get a positive kill ratio without ksing.

Edit Note : Ever since Global ult nerf, Pantheon lost lots of ganking power but hes still fine as a middle champion and a excellent assassin. The only problem is building his late game correctly.

Pantheon is a bursting assassin. Many people play him as a auto attacker. I however play him as a AD burst mage depending on E's and W's. With my masteries and items, Pantheon's E can hit 4 second CD and W 6 seconds, allowing me to constantly nuke.

Q - Up once at start to harass enemy champions. Try not to last hit with this if you can help it as it is a better use on enemy champions. Wasting 45 mana per minion is a drag, even with MP regens.

W - Up this once during lvl 2/3. I put this up during 2 for laning phase 2v2, ensuring a kill at level 3 or a surprise bush gank.

E - My favorite skill. Up this like a boss. Anytime you can, get this skill as it is invaluable, even with the nerf (its a nerf/buff but w.e)

R - Super flash with 5500 range. Allows super ganks and since the Pantheon patch, his R is significantly faster at casting and hitting. I always landed by R's but w.e, the damage ratio buffer is nice too.

My skill combo is W auto attack E auto attack Q -> lowers to 40%(carry)/60%(tank) gg unless tenacity
Later game with lots of CDR and mana Q W E Q W E Q W E -> pretty much GG unless tenacity + team

Q's are alot stronger then the older Pantheons Q but its scaling has been weakened 20%. Do not rely on this skill early game, rather use this later on for starting combos or ending chasers.
W's are super OP and amazing. Each W is a auto attack shield block and a set up for E. Do not waste W's on tanks and always aim for the carry.
E's are OP. Garen's E < Pantheon's E. The only problem with this skill is that if your CC'd during duration, your cooked unless you have a reliant team.

Don't follow my skill tree exactly because certain situations call for adaptation.
"It is not the strongest of the species that survive, nor the most intelligent that survives. It is one that is most adaptable to change." - Charles Darwin

During lane phase, stay aggressive. Constantly Q the enemy champion unless your facing some OP insta lock harassing champions. If you use my mana rune page, you should be able to stay in lane for a long time. Play smart as you are aggressive. Don't QQ about how my build sucks when you can't dodge Karthus's Q's and you don't suspect their Alistar of having stun and headbutt.
Out smart the enemy while tossing your spears.

If facing skill shotters (Lee sin, Ezreal, Nidalee):

stay behind minions
make sure to minion last hit when the minion is low as 10%. Do not use Q's on minions unless you can't help it and thats the only way to get a minion in.

If facing jumpers (jax,kat,akali) :

stay sharp, keep away from minions and keep your distance as they have a bigger range then your Q/W.
when they get bolder and your level 4, just sit behind your minions, and allow them to "jump on you" while your minion tide is infront and another coming from behind. W E Q gg usually

If facing super range (ashe,brand,karthus's) :

DO NOT sit next to your minions
keep alert to dodge their skills
once they are out of mana, WHOMP them

Long Sword -> sets up a early game Q/E damage
Boots -> sets up a kill in lane phase usually
Brutalizer -> Sets up GG E nukes (until lvl 10ish or enemy gets armor)
BF Sword -> GG early game, best time to get this item [9:00]
or
Pickaxe -> slowly building GG status. get this or BF at [9:00]
Infinity Edge -> E is decimating and stragglers get W'd, and then auto critted to death.
Frozen mallet -> provides valuable health, decent damage and a constant slow, making you in charge of the team fights. Tell team to keep you alive, focus carries
Banshee -> keeps you alive, get sooner if enemy is a mage
Youmu -> finish that brutalizer and start terrorizing. Get a avarice blade early game if you have the income.
Last Whisperers -> no tank can escape without losing a chunk of their health, and carries will get nuked by a W E combo.

If situation calls or situation is perfect
BloodThirsters -> your winning and you want to decimate harder, replace with youmu
Banshee -> your losing to a mage, inform team of all getting one so they can stand a chance
Thornmail -> do not get unless enemy Tyrnd/Xin/Yi is hitting over 300 without crits, otherwise useless unless the enemy team is compromised of all AD champions
Atmogs -> Warmog/Atma combo. Replace Banshees and Youmu for Atmogs. Only get if you need late game sustainability.

Spells that work with Pantheon (having one of these is a MUST) :
Ghost Ignite Exhaust Cleanse
Reasons : Pantheon has NO natural escape mechanisms( his ult works but I prefer not to waste that). Having ghost makes him a great chaser/escape artist. If mid-laning or you want extra damage Ignite is a must have. Exhaust is great for helping you aim E and cleanse works as a get out of jail or stun free card after jumping a enemy.

Spells that are OK with Pantheon :
Teleport Heal Rally Flash Revive
Reasons : Pantheon has a global teleport already and if you have Ionian boots, the CD isnt much of a problem. Heal is for the unsure Cautious players. Rally procs pretty well for the extra damage boost early game and for his late game E. Flash in my opinion takes too long to cool down, might be removed soon, and procs cockiness. Revive is great for the times when you accidentally get aced and need to clear a tower.

Spells that aren't very effective with Pantheon (at least in my build) :
Clarity Smite
Reasons : I personally dont have Mana troubles with Pantheon so I don't pack clarity and smite is pretty worthless on Pantheon unless your jungling.

The only runes you need on Pantheon is the CDR and the armor pen. You could choose to alter his seals with armor/dodge and even change his arp quints to hp quints but I recommend only changing his seals.

As for masteries I don't put one on ghost/exhaust or any summoner skill in general because I like to keep my Pantheon adaptable for Ranked games and I'm terribly lazy.
Critical damage mastery is beautiful with Pantheons E passive and with Infinity Edge... GG.
I put 3 on perservance to lane longer and 2 on good hands to quickly bounce back up ( Maxing this is only for people who plan to die alot).

If your playing Dominion, go with armor seals instead of mana regen.

Pro :
AD Burster
Can block one auto attack including one turret, saving your life often
Can gank like no other (unless you can't aim your R)
R is semi glitchy, you can W before you land, causing a saumersault stun from 2 meters away.
(this isnt a glitch but a animation error, you actually land sooner then the animation, allowing you to run around)

Con :
Squishie AF
Late game sustainability and damage output will be significantly disminished unless built accordingly
I never had this problem but many of my friends and other Pantheons seem to have no mana in laning phase early game

Pantheon is a burst nuke AD carry assassin. Early game, your kill chance will be 80%. Late game, it will drastically fall to 40% unless your maximizing damage and surviving team fights.

Never EVER R into turret with more then 2 enemy champions inside its range, unless your team is there and you guys can ensure their deaths.