Far above the clouds on Mount Targon resides a stalwart tribe of people known as the Rakkor who still revere combat and war as ultimate artforms. They remember the Runewars of Runeterra and know that the League of Legends can only repress the rising tides of violence for so long. Each member of the tribe is bred to be a disciplined and vicious warrior, preferring to battle soldiers of either the Noxian or Demacian armies only when outnumbered at least ten to one. Rakkor warriors are trained not only to be as lethal with their bare hands as the most capable martial artists, but also to fiercely wield the many relic-weapons of the tribe. Such treasures have been handed down from generation to generation, and have harnessed the mystical nature of Runeterra in their very cores. These relic-weapons are among the most dangerous in existence - and it comes as no surprise that they have found their way to the League of Legends in the hands of Pantheon.
This stone-faced warrior is a paragon of his people, his very existence is an anthem of exultation to the art of combat. Pantheon found it insulting that the people of Valoran would install an organization to replace war, complete with so-called champions, without including the Rakkor. Gathering the blessings of his tribe and armed with the relics of his ancestors, he has descended on the League to show the world a true warrior. He cares not who he fights, and cares nothing for the pageantry or prestige of a League champion, but lives only for the austere glory of battle. As long as Pantheon breathes, he thirsts for another foe to vanquish.

"I was hoping they had more reinforcements."
― Pantheon, standing amidst the pieces of a brutalized Noxian battalion.

Aegis Protection is a passive ability that activates whenever Pantheon autoattacks or uses one of his champion abilities, granting him a stack of the Aegis Protection buff. Upon reaching 4 stacks, Pantheon gains a shield buff that will be consumed to block the next autoattack, enhanced attack, or turret shot that would deal more than 40 physical damage to him, negating all damage from that attack.
Aegis Protection will NOT negate on-hit effects from the attack that was blocked.
Aegis Protection will block autoattack modifying abilities, e.g. Siphoning Strike.
However, Poppy's Devastating Blow cannot be blocked. This may be due to Devastating Blow not doing any physical damage, which is the key component in triggering Aegis Protection.
Similarly, Mordekaiser's Mace of Spades cannot be blocked by Aegis Protection.
Aegis Protection will block abilities that proc on-hit effects, e.g.:
Fizz's Urchin Strike
Fiora's Blade Waltz
Gangplank's Parrrley
Ezreal's Mystic Shot

Spear Shot is a single targeted ability that hurls a spear at a target enemy unit, dealing physical damage on impact.
Spear Shot does not proc on-hit effects.
Spear Shot procs spell vamp and Rylai's slow similarly with all single target spells and abilities with full effect.
Spear Shot pops Spell Shield.
Spear Shot will not damage Black Shield.
If Pantheon has at least one point in Heartseeker Strike, Spear Shot will "crit" to deal 150% damage on enemies at or below 15% of their maximum health.
Spear Shot will only "crit" if Pantheon has at least one skill point spent on Heartseeker Strike, and is not enhanced in any way by critical strike enhancing items such as Infinity Edge.

Aegis of Zeonia is a single targeted dash ability that causes Pantheon to leap to a target enemy champion's location, dealing magic damage and stunning it upon arrival. Pantheon will be placed slightly in front of the target. Upon activation Aegis Protection will also be fully charged.
Aegis of Zeonia does not proc on-hit effects.
Aegis of Zeonia procs spell vamp and Rylai's slow similarly with all single target spells and abilities with full effect.
Aegis of Zeonia pops Spell Shield.
Aegis of Zeonia will damage Black Shield and the stun is negated.
Pantheon can be affected by Crowd Control during Aegis of Zeonia's leap, and the ability will be canceled.
Aegis of Zeonia allows Pantheon to move over walls.
If the target uses Flash or other movement abilities while Pantheon is mid-leap, Aegis of Zeonia will not track the movement and Pantheon will move to the target's original location. However, they will still take its damage and be stunned.

When Heartseeker Strike is first leveled, Pantheon also gains the Certain Death passive ability. Certain Death passively allows Pantheon to deal 150% damage with Spear Shot or gain a 100% chance to critically strike on his autoattack against enemy units at or below 15% of their maximum health.
Heartseeker Strike is a channeled conic area of effect ability that initiates a 0.75 second channel. While channeling, every 0.25 seconds all enemy units in the target area in front of Pantheon take physical damage. This damage is doubled against champions.
Heartseeker Strike does not proc on-hit effects.
Heartseeker Strike procs spell vamp and Rylai's slow similarly with all area of effect spells and abilities with diminished effect.
Heartseeker Strike pops Spell Shield.
Heartseeker Strike will not damage Black Shield.
Heartseeker Strike is channeled over 0.75 seconds, and can be interrupted by crowd control.
Heartseeker Strike will apply The Black Cleaver's debuff up to 3 times when used. [1]

Grand Skyfall is a ground targeted point blank area of effect channeled blink ability that initiates a channel for 2 seconds. If the channel completes, Pantheon teleports to the target location, dealing magic damage and slowing all enemy units within the area after a 1.5 second delay. Grand Skyfall deals reduced damage to enemies further away from the center of the AoE.
Grand Skyfall procs spell vamp and Rylai's slow similarly with all area of effect spells and abilities with diminished effect.
Grand Skyfall pops Spell Shield.
Grand Skyfall will damage Black Shield and the slow is negated.
Grand Skyfall's channel can be interrupted by crowd control.
If Grand Skyfall's channel is interrupted or manually canceled, its cooldown is reduced to 10 seconds. The mana cost of the cancelled cast is not refunded.
After the initial channel, Pantheon is considered to have moved to his target location.
Area of effect abilities such as Viktor's Gravity Field can still affect Pantheon during this time. Grand Skyfall's impact damage/slow will still occur even if Pantheon is disabled.
Aegis of Zeonia's command can be shift-queued upon an enemy champion in the target location, and if the channel completes Pantheon will perform Aegis of Zeonia even if the target champion is outside the casting range, but this will cause Grand Skyfall to deal no damage.