Pantheon's builds don't seem to accommodate well for his propensity to burn out his mana in about 1-2 spell rotations, even in late-game, emphasizing that he needs damage, more damage, and a hint of durability. But getting a Frozen Heart on him? "Report Panth, trolling."
Intended intrinsic problem?
SGT Dingle Berry1 votesTry stealing the enemy blue as often as possible.
Outdated1 votesRough feels.
I enjoy a spammy ability-centric playstyle on just about every AD-mana-having champion. But, except for the small subset that actually excels with Manamune, Essence Reaver all the mana items seem like a trap. Sheen 
& Glacial Shroud 
completions have broader applicability, and aren't as bad as aforementioned items but is still going to under perform other canonical completions such as Yomuu's & Black Cleaver.
I very much enjoy Righteous glory but that build always ends up a trap. It really will not help you win anything that a similar value AD or even traditional tank item might.
Try switching out your glyphs for scaling mana regen or a combination of flat & scaling mana regen.
Otherwise I've seen a variety of players listed on probuilds.net get varying levels of Meditation with 1 point being a common practice.
