This is a list of all skill point locks and unique equipment, which have pre-set stats that are always the same every time you play, prior to patch 1.06 would result in items with no abilities if dropped from revenants.

This does not include anything from Way of the Strong, or the new patch 1.06 missions, although I don't think the 1.06 missions have anything unique (but I haven't played them yet).

This will take multiple posts, so please wait until I finish to post.

Young Samurai's Locks:
-UNKNOWN (somewhere in region 1)
-Isle of Demons mission: amrita on a cliff near the second shrine
-Deep in the Shadows: amrita behind the Nurikabe past the second shrine
-The Silver Mine Writhes: small chest in side room on upper level of third poison pit
-Falling Snow: amrita in area past building near first shortcut door (a short way past the first ice crystal)
-The Defiled Castle: amrita in corner with two dwellers and a mudman in area opposite the second purple crystal
-Immortal Flame: chest in the middle of fire near the shortcut back to the first shrine (reach via Nurikabe wall and waterside path)
-Sekigahara: amrita in the middle of the cannon-blasted battlefield, near a couple of other amrita (on the other side of the battlefield from the second shrine)
-The Source of Evil: amrita on corpse behind the building near the first Onryoki (found between first and second red crystals)
-Main mission reward: Memories of Death-Lilies
-Mission reward: Death to Bandits
-Mission reward: Invitation from the Warrior of the West
-Mission reward: A Bridge of Bone
-Mission reward: The Way of the Warrior (Novice)


Young Ninja's Locks:
-Deep in the Shadows: amrita in the cave passage between levels around the third shrine
-The Spirit Stone Slumbers: amrita near the second underground shrine, behind sentry statues
-The Ocean Roars Again: small chest in the far corner to the right of the boss door
-The Demon of Mount Hiei: amrita past second shrine, under the bridge above the path
-The Iga Escape: amrita in the rafters up a ladder after riding the spiked ceiling up two floors (after inverting the mansion)
-Immortal Flame: chest on the terrace near the Storehouse Key locked building (drop down from the upper roof with the gunner)
-The Source of Evil: amrita near the Onyroki between the first and second red crystals
-Mission reward: The Three Angry Gods
-Mission reward: Of Withered Grass and Yokai
-Mission reward: The Way of the Ninja (Novice)


Young Onmyo Mage's Locks:
-The Silver Mine Writhes: small chest on mid level walkway of final poison pit (drop from the upper level)
-The Ocean Roars Again: small chest at the end of the left pier at the intersection past the big doors
-The Demon of Mount Hiei: amrita in third crystal pit, right outside of the crystal room to the left
-Memories of Death-Lilies: small chest in the building on the left a short ways before reaching the temple doors
-A Defiled Holy Mountain: amrita in guard post on cliff face on upper path near hot spring
-Mission reward: The Guardian of the Underworld
-2x Mission reward: The Fallen Onmyo Mages
-Mission reward: The Way of Onmyo (Novice)


Master Samurai's Locks:
-Spider Nest Castle: amrita in the alley far to the left of the third shrine
-Immortal Flame: chest in the small building unlocked by the Storehouse Key past the fire field after the second shrine
-A Defined Holy Mountain: amrita on a cliff near the second shrine (must drop down from above)
-Mission reward: Heir to the Nioh
-Mission reward: Demon Hunting
-Mission reward: The Okehazama Incident
-Mission reward: The Demon's Daughter

Master Ninja's Locks:
-Spider Nest Castle: amrita in the basement cavern, near a skeleton and a developer revenant
-The Iga Escape: chest behind a fake wall on the right side of the final corridor before the boss (with a green crystal blocking the way)
-Immortal Flame: amrita behind a breakable wall shortly before the bridge to the second shrine (use fire to blow up the gunpowder barrel)
-Mission reward: The Ogress
-Mission reward: The Giant Frog Brawl


Master Onmyo Mage's Locks:
-Falling Snow: chest in the rafters of building with third ice crystal (there is a ramp to the roof just outside)
-The Source of Evil: amrita behind the guard tower near the third crystal
-Mission reward: The Disappearing Ranjatai
-Mission reward: The Way of Onmyo (Adept)


Famed Samurai's Locks:
-The Demon King Revealed: amrita beside the well near the first yokai rush, atop the hill past the door next to the starting shrine
-Mission reward: The Inheritance


Famed Ninja's Locks:
-The Iga Escape: in a chest down a secret trapdoor after the wind Amrita Fiend on thed second floor (just before going outside)
-The Demon King Revealed: amrita behind wall near second yokai rush, reach via secret path around base of the structure
-Mission reward: A True Ninja


Famed Onmyo Mage's Locks:
-The Demon of Mount Hiei: unsure of specific location, late in the level somewhere
-The Demon King Revealed: amrita on hidden ledge behind shortcut door near first shrine
-Mission reward: A Greater Harmony (Onmyo mystic art)


Unique equipment:
-Fire Omamori Charm L5: Isle of Demons, amrita guarded by a dweller in back alley
-Archer Armor set L12: Deep in the Shadows, found across four amrita across the final area with the third shrine
-Paralysis Omamori Charm L12: Deep in the Shadows, in chest behind ledge far past third shrine
-Vassal's Armor set L19: The Spirit Stone Slumbers, 3 in chest near east gate key, 2 in chest near second shrine
-Oak Hammer L18: The Spirit Stone Slumbers, in chest near second shrine (same as 2 Vassal Armor pieces)
-Senjuin Tachi L25: The Spirit Stone Slumbers, in a chest near the end of the underground ruins in a small room with three chests
-Poison Omamori Charm L27: The Silver Mine Writhes, small chest next to secret hot spring
-Ambush Unit Armor set L27: The Silver Mine Writhes, all 5 in secret chest near boss (drop down from upper level onto a rock near the fragile bridge)
-Foreigner's Armor set L55: Falling Snow, 2 in chest near second shortcut door, 3 in chest behind shortcut door near final ice crystal
-Taima Kuniyuki L55: Falling Snow, amrita in enclosed area near 3rd shrine (approach from roof of nearby building)
-Eight Divine Weapons from Yamata-no-Orochi L150: Kusanagi Tsurugi, Kogarasu-maru and Nuke-maru, Ningen Mukotsu, Haja the Evil-Crusher, Rasatsu Kusarigama, Tate-ugachi Bow, Sakai Rifle, Ginshu Hand Cannon

First-time mission reward equipment:
Story missions:
-1: Isle of Demons: Tanegashima Matchlock L11
-2: Deep in the Shadows: Legendary Strategist's Garb: Zukin L18, Hand Cannon L18
-3: The Spirit Stone Slumbers: Raikiri L25
-4: The Silver Mine Writhes: Usurper's Kabuto L33
-5: The Ocean Roars Again: Omamori Charm L44
-6: Spider Nest Castle: Fan L53
-7: Falling Snow: Gyukaku-Jumonji Spear L60
-8: The Demon of Mount Hiei: Onmyo Mage's Hunting Gear: Joi L67, Onmyo Mage's Hunting Gear: Eboshi L67
-9: The Iga Escape: Jonin's Kusarigama L76
-10: Memories of Death-Lillies: nothing
-11: The Defiled Castle: Medicine Case L93
-12: Immortal Flame: Hikoemon Ichimonji L102, Fanatic's Armor (M): Kabuto L102
-13: Sekigahara: Oni Sakon's Spear L107
-14: The Source of Evil: Slayer's Axe L117
-15: A Defiled Holy Mountain: Magatama L126
-16: The Samurai from Sawayama: nothing
-17: The Demon King Revealed: nothing (L150 divine weapon set from Yamata-no-Orochi)
-18: The Queen's Eyes: nothing

Region 1 sub-missions:
-Death to Bandits: Bandit Axe L12, Minoden Dual Tachi L12
-Wreathed in Flame: Mikazuki Kusarigama L15
-Finders, Keepers: Ikkoku Nagayoshi Spear L17, The Raging Bull: Hizayoroi L17
-Kanbei and the Overlord: Heshikiri Hasebe L19
-A Request from Ginchiyo: nothing
-Invitation from the Warrior of the West: nothing

Region 2 sub-missions:
-The Guardian of the Underworld: nothing
-The Three Angry Gods: nothing
-The Magatama of Fire: nothing
-The Bridge of Bone: Ambush Unit Armor (M): Suneate L40
-Heir to the Nioh: Furiwakegami Hiromitsu L45
-The Conspirators: Atagi Sadamune L47

Region 3 sub-missions:
-The Ogress: nothing
-The Battle of Ohashi Bridge: Shura's War Axe L47
-The Disappearing Ranjatai: Fudo Kuniyuki & Yagen Toshiro L51
-Demon Hunting: Red Demon Armor (L): Kabuto L54, Red Demon Armor (L): Kote L54
-The Malefactors: Yogarasu Kusarigama L58
-The Red Oni of the Ii: Akaoni-no-Sankaku Spear L60, Fire Omamori Charm L60
-The Fallen Onmyo Mages: nothing
-The Missing Catalog: nothing
-Greater Demon Hunting: Doji-kiri Yasutsuna L72, Kaido Armor: Do L72

Region 4 sub-missions:
-The Three Souls: Woman's Face Visor L67
-Of Withered Grass and Yokai: Tengu Face Visor L73
-A Fiercer Flame: Fire Omamori Charm L74
-The Trail of the Master: nothing
-The Seven Good Tidings: Kodama Bowl L80
-The Okehazama Incident: nothing
-The Rising Shadows: nothing
-The Giant Frog Brawl: nothing
-The Champion of the East: Tombo-kiri L95, Prayer Beads L95

Region 5 sub-missions:
-The Silent Crow: Bellowing Tenryu L92
-The Unrepentant Thief: Braided Straw Kabuto L93
-Desperate Retreat: Sohaya Tsurugi L109
-Kuroda's Determination: Ichi-no-Tani Kabuto L109
-The Demon's Daughter: Scorpionfish Kabuto L115
-The Watcher in Darkness: Ravenwing Rifle L117

Region 6 sub-missions:
-Master of the Twin Blades: Dual Wooden Swords L120, Takezo's Headband L117 (headband given during mission)
-The Mountain of Remorse: Vengeful Spirit Visor L126
-The Ghosts of Sawayama: Hinomotogo L132
-The Inheritance: Bellflower Kabuto L134
-The Two Kings: Nioh: Shiranui L141, Prayer Beads L141
-A Meeting on the Other Shore: Sozasa Monji L143, Fan L143

Dojo training missions:
-Warrior (Novice): Wooden Sword L20
-Ninja (Novice): Shinobi Apparel: Hakama L11, Shinobi Apparel: Joi L11, Shinobi Apparel: Zukin L11
-Onmyo Mage (Novice): Onmyo Mage's Suikan: Joi L25, Onmyo Mage's Suikan: Tekko L25, Onmyo Mage's Suikan: Hakama L25
-Warrior (Adept): Genius Strategist's Garb L40, Genius Strategist's Hakama L40
-Sword Mystic Art: Tengu-kiri L100, Fire Omamori Charm L100
-Dual Swords Mystic Art: Futatsu-mei Norimune & Hone-bami Toshiro L100, Lightning Omamori Charm L100
-Spear Mystic Art: Hozoin Jumonji Spear L100, Water Omamori Charm L100
-Axe Mystic Art: Kaido Axe L100, Earth Omamori Charm L100
-Kusarigama Mystic Art: Shishido Kusarigama L100, Wind Omamori Charm L100
-Ninja Mystic Art: Poison Omamori Charm L123, Paralysis Omamori Charm L123
-Onmyo Mage Mystic Art: Prayer Beads L???


Notably, the unique item drops from a mission (equipment and even normal items, like locks, Summoner Candles, etc.) only occur ONCE on a character, and seem to be shared between Samurai, Strong, and twilight missions. You can get the Young Samurai's Locks near the second shrine in Isle of Demons whether you play it on Samurai, Strong, or the twilight variation of either, but you ONLY find it once. After that, it will just be a Small Spirit Stone.

If you wait until Way of the Strong to pick up unique equipment, it will be level 150, but still stuck at its normal rarity. Unique equipment will only appear in the normal version of a mission, not twilight version.

Some of the unique stuff has entirely unique aspects that can never be duplicated:

-Fire Omamori Charm in Isle of Demons does not have Vs. Fire as a locked ability. Same for Paralysis Omamori Charm in Deep in the Shadows, and Poison Omamori Charm in The Silver Mine Writhes.

-The Archer armor set in Deep in the Shadows does not have Bow Damage as a locked ability, and it is higher than the usual value (this set is 6.0%+, unlike the normal Archer pieces with just 5.0%). Each piece also has Unlimited Ammo on it, even though usually only the arms can get that ability.

-Kogarasu-maru & Nuke-maru dropped from Yamata-no-Orochi does not have the locked Spirit Protection (Yatagarasu).

-The three ranged weapons from Yamata-no-Orochi each have Retrieve Stray Projectiles ability, which is green and cannot be acquired on any other ranged weapon. That's 5 total actually unique weapons YNO drops.

-Sozasa Monji won from A Meeting on the Other Shore does not have the locked Strong Attack Damage. (it doesn't have that ability at all, in fact). If you wanted CCD+15% or some other damage ability on the National Unity weapon, this is your only chance.