The purpose of this build is to allow pantheon to be what he is(an early/mid game carry and late game anti-carry) while giving him as much utility and survivability as possible. Having a ton of mana regen makes laning amazing, and getting the chalice is often not needed, it just depends on who you are laning against and how much gold you have when you go back the first few times. The armor pen runes and a fairly early brutalizer gives you all the ARP and damage you need to be a serious threat to any squishy. The problem I have had is that when going full dps builds, sure you can do some insane damage, but the later the game goes on the less viable you become. However, with getting a warmogs and atmas, even though your damage will fall off for a bit, you eventually will pack quite a punch AND be a beefy mofo. This is what I have used for every ranked game I have played with him once it was tested enough in normals, and it has yet to fail me. Even the games My team doesn't do so good, or I seem to be focused hardcore, I still end up having a possitive K/D ratio. Also keep in mind that with your ulti you have so much map control its almost unfair, not to mention the threat of you pushing 1 lane, the porting to another and doing some serious tower damage (rushing youmuu's before finishing warmogs and atmas to further fill a tower pusher role is perfectly fine). So please if you decide to look at this guide and see the purpose of it and try it, let me know how it goes before grading it, I know its not the most descriptive build out there but its all i feel like doing for now, TY and GL.