Path of Pain
Choosing to embody suffering rather than merely tolerate it, those consumed by pain are rewritten by it: avatars of its cruelty, often disfigured by the brutality they endure. Those sentinels who follow the Path of Pain feed upon their misery, charged by the dark side to withstand extremes of punishment and to spread their agony far and wide.
Embodiment of Pain
Path of Pain: 3rd level
You learn the force body force power, which does not count against your total powers known. You can cast it without expending force points.
Additionally, when you gain temporary hit points from a universal or dark-aligned force power or one of the features of this subclass, you can draw from those temporary hit points instead of your hit points when utilizing force body's effects. When you do so, and you expend temporary hit points and none of your hit points, you do not suffer reduction to your maximum hit points.
Sustenance of Suffering
Path of Pain: 3rd level
When you take damage, you can choose to gain a number of temporary hit points equal to half the damage taken (rounded down). You cannot gain these hit points if the triggering damage would reduce you to 0 hit points, and the temporary hit points do not affect the triggering damage taken.
While you have these temporary hit points, and you deal damage with a melee weapon attack or dark-aligned force power that targets only one creature, you can expend a number of the temporary hit points (no action required) to deal additional damage of the same number. You can expend temporary hit points up to your proficiency bonus, as seen in the Sentinel table.
You can use this reaction a number of times equal to your proficiency bonus, and again if you expend a use of your Ideal Manifests.
Merciless Misery
Path of Pain: 7th level
Once on your turn, while you have temporary hit points from Sustenance of Suffering and you make a weapon attack, you can expend 4 temporary hit points to make an additional attack as part of the same action.
Additionally, while you are suffering from at least one condition among corroded, disease, exhaustion, ignited, poisoned, shocked, slowed, or weakened, you have advantage on your damage rolls with melee weapon attacks and dark-aligned force powers.
Fractured Existence
Path of Pain: 13th level
When you would be reduced to 0 hit points, you can expend a use of your Sustenance of Suffering or Ideal Manifests (no action required) to have 1 hit point instead.
Additionally, when you take damage from a source you can see and don't use Sustenance of Suffering, you gain advantage on your next attack roll before the end of your next turn.
Perpetual Pain
Path of Pain: 18th level
When you make a weapon attack or dark-aligned force power attack roll and roll a natural 20, or a creature rolls a natural 1 on the saving throw against a dark-aligned power you control, they suffer a stack of Perpetual Pain (to a maximum of 5 stacks). Constructs and creatures immune to psychic damage are immune to Perpetual Pain, and it can be immediately removed by the restoration force power.
A creature with stacks of Perpetual Pain suffers 1d4 necrotic damage per stack at the beginning of their turns and again each time they make a weapon attack or cast a power using an Action. If a creature dies from this damage, you gain temporary hit points equal to your sentinel level, which you can use as though they were gained by Sustenance of Suffering.
A creature within 5 feet of the creature suffering from Perpetual Pain can use an Action to make a Medicine check, DC equal to your force save DC. On success, one stack of Perpetual Pain is removed.
A creature does not take beginning-of-turn damage from Perpetual Pain when not in combat, but any stacks persist until removed.