This is the Pantheon build that I personally use for Dominion. It gives good a good amount of damage, crit, and health, not to mention utility. I have really only been playing Pantheon since Dominion came out and I kept getting so annoyed by how good Pantheon seemed to be (with the jumping about messing things up). He is an amazing Dominion champion when played correctly. Making timely use of his ultimate is crucial, in addition to know when and who to jump on with Q for the stun (this can make or break a fight).

Standard armor pen marks. I like to take four 4 % seals with 5 health per level seals. Gives a good amount of health late game. For glyphs I like to go with cdr because it helps panth so much. Movement quints because it makes a big difference, especially in dominion.

For his mastery tree I like to go 22/8/0. I take the damage and armor pen, plus the extra 4 points in cdr, because cool downs are important for Panth. I like to get the crit and go straight down the damage, skipping the lifesteal because that isn't what you are about. You are a jumping, poking, crit monster. Use your Q when they think they are getting away....

For my items I like to start with Prospectors sword because, for the price, you can't beat that health/damage/lifesteal, it would be silly to not get it, in my opinion. Then you go brutalizer/boots, usually the same trip. Get your slow with Entropy so that when you jump on them and poke they don't get silly and run away. I've altered the build from what it used to be to include a much heavier focus on dealing damage, as opposed to the offtank dps that I had built before. This has worked much better for me, especially the change from Frozen Mallet to Entropy. As long as you remember to activate it, Entropy, it is a lot more bang for you buck then Frozen Mallet.

I take Ghost because it's dominion and you're top, or should be, and you need Ghost. It's amazing for joining team fights, saving a tower, etc. I like exhaust because it just shuts down that hard dps'r that you are trying to kill for your team. He can't get away, omg, he's dead.